[求助]新东方讲义上的真题

it is crucial important to farmers that the herbicide they used to control weeds not damage their crops. one very effective herbicide is safe fot corn, but soybeans are damaged even by the herbicide's residue, which remains in the soil more than a year after the herbicide is applied. soybeans and corn are not sown together in the sameriled; nevertheless, most farmers are reluctant to use the herbicide on their own corn.

which of the following, if true, provides the strongest justification for the farmers' reluctance?

A the residue of the herbicide in the soil a year after application is not enough to control most weeds effectively.

B to maint ain the nutrients in the soil, corn and soybeans are often planted in a riled in an althernate year.

C the demand fot soybeans is growing faster than is the demand fot core.

D for maximum yield, soybean plants are grown closer together to each other than are corn plants.

E the application of herbicides is less crucial for soybean than forcorn crops.

The answer of this question is A. I chosed B.