water fertilizer herbicide insecticide
I gave my students this multiple choice question: Bacillus thuringiensis (Bt) is a soil bacterium that is toxic to certain insects. Genes from this bacterium have been inserted into cotton to make Bt cotton. Farmers that use Bt cotton would most likely use less of which of the following?

Only one answer is correct among these 4 choices:
- water
- fertilizer
- herbicide
- insecticide

Could you tell me which one is correct?

insecticide