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Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
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Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Which of the following can be inferred from the theory of periodic extinction mentioned in paragraph 3?

A. many scientists could be expected to disagree with it.

B. most scientists believe the theory to be accurate.

C. the theory is no longer seriously considered.

D. evidence to support the theory has recently been found

1
20 tháng 8 2019

Đáp án A

Dịch nghĩa: Từ học thuyết tuyệt chủng chu kì được đề cập ở đoạn 3 có thể suy ra điều gì?

A. rất nhiều nhà khoa học có thể phản đối nó.

B. hầu hết các nhà khoa học tin học thuyết này là đúng.

C. học thuyết này không còn được xem xét một cách nghiêm túc nữa.

D. bằng chứng để ủng hộ học thuyết này đã được tìm ra.

Giải thích: Thông tin nằm ở “The periodic extinction might be due to intersection of the earth’s orbit with a cloud of comets, but this theory is purely speculative”. Vì nó hoàn toàn là suy đoán nên ta có thể suy đoán rằng nó bị nhiều nhà khoa học khác phản đối.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42. It is estimated that by 2050 more than two-thirds of the world's population will live in cities, up from about 54 percent today. While the many benefits of organized and efficient cities are well understood, we need to recognize that this rapid, often unplanned urbanization brings risks of profound social instability, risks to critical...
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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.
 
It is estimated that by 2050 more than two-thirds of the world's population will live in cities, up from about 54 percent today. While the many benefits of organized and efficient cities are well understood, we need to recognize that this rapid, often unplanned urbanization brings risks of profound social instability, risks to critical infrastructure, potential water crises and the potential for devastating spread of disease. These risks can only be further exacerbated as this unprecedented transition from rural to urban areas continues.
How effectively these risks can be addressed will increasingly be determined by how well cities are governed. The increased concentration of people, physical assets, infrastructure and economic activities mean that the risks materializing at the city level will have far greater potential to disrupt society than ever before.
Urbanization is by no means bad by itself. It brings important benefits for economic, cultural and societal development. Well managed cities are both efficient and effective, enabling economies of scale and network effects while reducing the impact on the climate of transportation. As such, an urban model can make economic activity more environmentally-friendly. Further, the proximity and diversity of people can spark innovation and create employment as exchanging ideas breeds new ideas.
But these utopian concepts are threatened by some of the factors driving rapid urbanization. For example, one of the main factors is rural-urban migration, driven by the prospect of greater employment opportunities and the hope of a better life in cities. But rapidly increasing population density can create severe problems, especially if planning efforts are not sufficient to cope with the influx of new inhabitants. The result may, in extreme cases, be widespread poverty. Estimates suggest that 40% of the world's urban expansion is taking place in slums, exacerbating socio-economic disparities and creating unsanitary conditions that facilitate the spread of disease.
The Global Risks 2015 Report looks at four areas that face particularly daunting challenges in the face of rapid and unplanned urbanization: infrastructure, health, climate change, and social instability. In each of these areas we find new risks that can best be managed or, in some cases, transferred through the mechanism of insurance.
Question 36: The word “that" in paragraph 4 refers to __________.
​A. urban expansion ​​B. socio-economic disparities
​C. disease  ​D. unsanitary conditions
Question 37:According to paragraph 3, what is one of the advantages of urbanization?
​A. It minimizes risks for economic, cultural and societal development.
​B. It makes water supply system both efficient and effective.  
​C. Weather and climate in the city will be much improved.
​D. People may come up with new ideas for innovation.
Question 38:Which statement is TRUE, according to the passage?
​A. Urbanization brings important benefits for development as well.
​B. 54% of the world's population will live in cities by 2050.
​C. Risks cannot be addressed effectively no matter how well cities are governed.
​D. Rapidly increasing population density can help solve poverty.
Question 39: The word "addressed" in paragraph 2 is closest in meaning to _________.
​A. aimed at ​B. dealt with ​C. added to ​D. agreed on
Question 40: What can be inferred from the passage?
​A. Poverty may be a foregone conclusion of unplanned urbanization.
​B. Diseases are caused by people migrating to cities.  
​C. Urbanization can solve the problem of environmental pollution in cities.
​D. The increasing number of people in cities can create more employment.
Question 41: Which is the most suitable title for the passage?
​A. The Risks of Rapid Urbanization in Developing Countries
​B. Infrastructure and Economic Activities in Cities
​C. The Global Risks 2015 Report on Developing Urban Areas
​D. Rapid Urbanization Put Cities in Jeopardy
Question 42: The word “spark” in paragraph 3 is closest in meaning to ___________.
​A. need ​B. start ​C. encourage ​D. design

1
17 tháng 6 2021

Question 36: The word “that" in paragraph 4 refers to __________.
​A. urban expansion ​​B. socio-economic disparities
​C. disease  ​D. unsanitary conditions
Question 37:According to paragraph 3, what is one of the advantages of urbanization?
​A. It minimizes risks for economic, cultural and societal development.
​B. It makes water supply system both efficient and effective.  
​C. Weather and climate in the city will be much improved.
​D. People may come up with new ideas for innovation.
Question 38:Which statement is TRUE, according to the passage?
​A. Urbanization brings important benefits for development as well.
​B. 54% of the world's population will live in cities by 2050.
​C. Risks cannot be addressed effectively no matter how well cities are governed.
​D. Rapidly increasing population density can help solve poverty.
Question 39: The word "addressed" in paragraph 2 is closest in meaning to _________.
​A. aimed at ​B. dealt with ​C. added to ​D. agreed on
Question 40: What can be inferred from the passage?
​A. Poverty may be a foregone conclusion of unplanned urbanization.
​B. Diseases are caused by people migrating to cities.  
​C. Urbanization can solve the problem of environmental pollution in cities.
​D. The increasing number of people in cities can create more employment.
Question 41: Which is the most suitable title for the passage?
​A. The Risks of Rapid Urbanization in Developing Countries
​B. Infrastructure and Economic Activities in Cities
​C. The Global Risks 2015 Report on Developing Urban Areas
​D. Rapid Urbanization Put Cities in Jeopardy
Question 42: The word “spark” in paragraph 3 is closest in meaning to ___________.
​A. need ​B. start ​C. encourage ​D. design

17 tháng 8 2018

Đáp án B

Kiến thức: Đọc hiểu

Giải thích:

Ý chính của đoạn cuối cùng là gì?

  A. Các nhà khoa học nghiên cứu về lão hóa đã kiểm soát quá trình lão hóa.

  B. Các nhà khoa học nghiên cứu về lão hóa đang làm việc chăm chỉ để giúp mọi người sống lâu hơn và khỏe mạnh hơn.

  C. Các nhà khoa học nghiên cứu về lão hóa đang cố gắng mang lại cho con người một cuộc sống vĩnh cửu.

  D. Các nhà khoa học nghiên cứu về lão hóa hiện có thể làm chậm quá trình lão hóa.

Thông tin: They are trying to discover how this clock works so that they can slow down the process. This could give man a longer life and a great number of productive years.

Tạm dịch: Họ đang nỗ lực tìm ra cách mà chiếc đồng hồ này hoạt động để có thể làm chậm đi quá trình này. Điều này có thể giúp cho con người sống lâu hơn và có được những năm tháng đóng góp nhiều hơn. 

II. Read the following passage and circle the letter A, B, C or D to indicate the correct answer to each of the questions from      It is estimated that about 200 million people who use Internet computer network around the world. Most people use the Internet to get information or for entertainment. A new study, however, says that almost 6% of Internet users are using it so often that it is seriously harming their lives. The study says these people may find it difficult to stop using the...
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II. Read the following passage and circle the letter A, B, C or D to indicate the correct answer to each of the questions from

     It is estimated that about 200 million people who use Internet computer network around the world. Most people use the Internet to get information or for entertainment. A new study, however, says that almost 6% of Internet users are using it so often that it is seriously harming their lives. The study says these people may find it difficult to stop using the Internet because they have become addicted. Someone who is addicted finds it extremely difficult to stop an activity. According to Mr. Greenfield, a psychologist, 30% Internet users say that they use the Internet to escape from problems or emotions. The study also shows that having discussions with strangers in Internet areas called “chat room” is one of the most addictive activities.

1. Most people use the Internet……………

A. for getting information      B. for entertainment     C. A and B are wrong.            D. A and B are correct

2. Some people use the Internet so often that………………..

A. they become more and more intelligent                 B. it is seriously harming their lives

C. it is good for their mind                                        D. they become computer programmers

3. When someone is addicted to the Internet………………

            A. they cannot stop using it easily                              B. they can stop using it easily

            C. they can get rid of it                                               D. they will become intelligent

4. According to Mr. Greenfield, 30% Internet users use the internet……………………

A. for entertainment              B. for getting information                                          

C. for chatting                      D. for escaping from problems or emotions

5. One of the most addictive activities is………………..

A. setting programs                 B. playing chess          C. chatting      D. getting information

D. WRITING: Complete the second sentence so that it has similar meaning to the first sentence.

1. These pupils  are hard-working so they get good marks for the test.

If …………………………………………………………………………………

2. John likes eating too much fast food, that’s why he is becoming fatter and fatter.

If …………………………………………………………………………………

3. Mai  doesn’t know the meaning of the words because she doesn’t have a dictionary.

If …………………………………………………………………………………

4. Children like to eat ice-cream. It can cause toothache if they have too much everyday. (which)

……………………………………………………………………………………

5. The gentleman in black is a famous writer. You met him at the party yesterday. (who)

…………………………………………………………………………………………

1
11 tháng 3 2023

II. Read the following passage and circle the letter A, B, C or D to indicate the correct answer to each of the questions from

     It is estimated that about 200 million people who use Internet computer network around the world. Most people use the Internet to get information or for entertainment. A new study, however, says that almost 6% of Internet users are using it so often that it is seriously harming their lives. The study says these people may find it difficult to stop using the Internet because they have become addicted. Someone who is addicted finds it extremely difficult to stop an activity. According to Mr. Greenfield, a psychologist, 30% Internet users say that they use the Internet to escape from problems or emotions. The study also shows that having discussions with strangers in Internet areas called “chat room” is one of the most addictive activities.

1. Most people use the Internet……………

A. for getting information      B. for entertainment     C. A and B are wrong.            D. A and B are correct

2. Some people use the Internet so often that………………..

A. they become more and more intelligent                 B. it is seriously harming their lives

C. it is good for their mind                                        D. they become computer programmers

3. When someone is addicted to the Internet………………

            A. they cannot stop using it easily                              B. they can stop using it easily

            C. they can get rid of it                                               D. they will become intelligent

4. According to Mr. Greenfield, 30% Internet users use the internet……………………

A. for entertainment              B. for getting information                                          

C. for chatting                      D. for escaping from problems or emotions

5. One of the most addictive activities is………………..

A. setting programs                 B. playing chess          C. chatting      D. getting information

D. WRITING: Complete the second sentence so that it has similar meaning to the first sentence.

1. These pupils  are hard-working so they get good marks for the test.

If these pupils are hard-working, they will get good marks for the test………

2. John likes eating too much fast food, that’s why he is becoming fatter and fatter.

If John didn't like eating too much fast food, he wouldn't become fatter and fatter……

3. Mai  doesn’t know the meaning of the words because she doesn’t have a dictionary.

If Mai had a dictionary ,she would know the meaning of the words ……

4. Children like to eat ice-cream. It can cause toothache if they have too much everyday. (which)

Children like to eat ice cream which it can cause toothache if they have too much everyday

5. The gentleman in black is a famous writer. You met him at the party yesterday. (who)

The gentleman in black who you met at the party yesterday is a famous writer

30 tháng 12 2018

Đáp án: A

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50. It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Question 43: The word "it" refers to ___________.

A. extinction

B. species

C. 99 percent

D. environment

1
23 tháng 12 2018

Đáp án B

Dịch nghĩa: Từ “it” nhắc tới ___________.

A. sự tuyệt chủng            B. loài                             C. 99%                    D. môi trường
Giải thích: Thông tin nằm ở “When a species is no longer adapted to a changed environment, it may perish” - Khi một loài không còn thích nghi với môi trường đã thay đổi, nó sẽ biến mất. Như vậy, nó ở đây chính là loài động vật đó.

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50. It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Question 49: Which of the following can be inferred from the theory of periodic extinction mentioned in paragraph 3?

A. many scientists could be expected to disagree with it.

B. most scientists believe the theory to be accurate.

C. the theory is no longer seriously considered.

D. evidence to support the theory has recently been found.

1
5 tháng 11 2018

Đáp án A

Dịch nghĩa: Từ học thuyết tuyệt chủng chu kì được đề cập ở đoạn 3 có thể suy ra điều gì?

A. rất nhiều nhà khoa học có thể phản đối nó.

B. hầu hết các nhà khoa học tin học thuyết này là đúng.

C. học thuyết này không còn được xem xét một cách nghiêm túc nữa.

D. bằng chứng để ủng hộ học thuyết này đã được tìm ra.

Giải thích: Thông tin nằm ở “The periodic extinction might be due to intersection of the earth’s orbit with a cloud of comets, but this theory is purely speculative”. Vì nó hoàn toàn là suy đoán nên ta có thể suy đoán rằng nó bị nhiều nhà khoa học khác phản đối.

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

     The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

     One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

 

Which of the following can be inferred from the theory of periodic extinction mentioned in paragraph 3?

A. many scientists could be expected to disagree with it

B. most scientists believe the theory to be accurate

C. the theory is no longer seriously considered

D. evidence to support the theory has recently been found

1
15 tháng 5 2019

Đáp án A

Dịch nghĩa: Từ học thuyết tuyệt chủng chu kì được đề cập ở đoạn 3 có thể suy ra điều gì?

A. rất nhiều nhà khoa học có thể phản đối nó.

B. hầu hết các nhà khoa học tin học thuyết này là đúng.

C. học thuyết này không còn được xem xét một cách nghiêm túc nữa.

D. bằng chứng để ủng hộ học thuyết này đã được tìm ra.

Giải thích: Thông tin nằm ở “The periodic extinction might be due to intersection of the earth’s orbit with a cloud of comets, but this theory is purely speculative”. Vì nó hoàn toàn là suy đoán nên ta có thể suy đoán rằng nó bị nhiều nhà khoa học khác phản đối.

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 21 to 25.I know that it is my job to make sure that everything goes well for the tourists and I feel I work hard for the company. I cannot be blamed for last week. I met the group at the airport and took them to the coach. The coach driver was a bit annoyed because the flight was late. But it wasn’t far to the hotel and everyone was looking forward to their dinner. We hadn’t...
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Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 21 to 25.

I know that it is my job to make sure that everything goes well for the tourists and I feel I work hard for the company. I cannot be blamed for last week. I met the group at the airport and took them to the coach. The coach driver was a bit annoyed because the flight was late. But it wasn’t far to the hotel and everyone was looking forward to their dinner. We hadn’t used the Hotel Riviera before but our normal one had a conference in it so it was fully booked. When I announced our arrival at the reception desk, they said they were full. I had booked rooms for the group but the manager said they were cancelled by phone a few days before. He insisted that he recognized my voice and that I had made the phone call. We had a bit of an argument but they obviously didn’t have enough rooms. In the end the manager phoned other hotels in the town and found rooms for everyone but in four different hotels. By this time, the coach had gone so we had to get taxis and some of the tourists started to get very angry with me. I still don’t know who made that phone call but it definitely wasn’t me.

0
Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50. It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Question50: In paragraph 3, the author makes which of the following statements about a species' survival?

A. it may depend on chance events.

B. it does not vary greatly from species to species.

C. it reflects the interrelationship of many species.

D. it is associated with astronomical conditions.

1
8 tháng 2 2018

Đáp án A

Dịch nghĩa: Ở đoạn 3, tác giả nói gì về sự tồn tại của một loài?

A. Nó có thể phụ thuộc vào những việc xảy ra tình cờ.

B. Nó không khác nhau nhiều giữa các loài.

C. Nó phản ánh mối liên hệ giữa các loài.

D. Nó liên quan đến điều kiện thiên văn học.