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Lê Quỳnh  Anh

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 35 to 42.

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Which of the following statements about the use of chemical agents as herbicides would the author most likely agree? 

A. It is safe but inefficient. 

B. It is occasionally required.

C. It should be increased. 

D. It has become more dangerous recently. 

Dương Hoàn Anh
3 tháng 7 2019 lúc 15:39

Đáp án B

Kiến thức: Đọc hiểu

Giải thích:

Tác giả có thể đồng ý với quan điểm nào sau đây về việc dùng chất hoá học làm thuốc trừ cỏ?

A. Nó an toàn nhưng hiệu quả không triệt để.

B. Nó thỉnh thoảng cần thiết.

C. Nên tăng cường sử dụng phương pháp này.

D. Gần đây nó ngày càng nguy hiểm.

Thông tin: The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary.

Tạm dịch: Nhu cầu kiểm soát cỏ dại trên thế giới chủ yếu được ngành công nghiệp hoá học đáp ứng. Thuốc diệt cỏ hoá học rất hiệu quả và đôi khi cần thiết. 


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