I have a quistion regarding the below: Which of the following would increase the supply of corn?

I have a quistion regarding the below:

Which of the following would increase the supply of corn? 

a.         an increase in the price of pesticides 

b.         a decrease in the demand for corn 

c.         a fall in the price of corn 

d.         a severe drought in the corn belt

e.         a decrease in the price of wheat

Answer: e

Q: Why isn't "a" a correct answer as well? aren't pesticides counted as "compliment" goods?