Question

Directions: Choose the sentence that best expresses the main idea of the selection.

"No pesticide can kill 100 percent of insects that are attacking a crop, and this poses a problem. Consider a pesticide aimed at insects that are attacking a particular crop. The pesticide may kill almost 100 percent of them, but thanks to the genetic variability of large populations, some insects are likely to survive the poison. The resistant insects can then multiply free of competition and produce many offspring that are resistant to the pesticide and can then attack the crop with new vigor. To control these resistant insects, a new and more powerful pesticide must be applied, and this produces a population of still more resistant insects. Consequently, still more pesticides and herbicides must be used."
Options:
A. No pesticide can kill 100 percent of insects attacking a crop.
B. Pesticides may lead to the evolution of resistant insects.
C. The use of pesticides and herbicides increases over time.
D. The genetic variability of insects leads to pesticide resistance.

Answer 1

The main idea is that pesticides may lead to the evolution of resistant insects.

Step-by-step explanation:

The main idea of the selection is that pesticides may lead to the evolution of resistant insects. Pesticides are designed to kill insects attacking crops, but due to genetic variability, some insects may survive and develop resistance to the pesticide. These resistant insects can then multiply and produce offspring that are also resistant, leading to the need for stronger pesticides. This process continues, resulting in the increased use of pesticides.