Farmers spray insecticides to protect their crops from herbivorous insects. What is the most likely effect of spraying the same insecticides continuously for many years?
A. The number of crops that carry a trait for insect resistance will increase.
B. The number of crops that do not carry a trait for insect resistance will increase.
C. The number of insects that are resistant to these insecticides will increase.
D. The number of insects that are not resistant to these insecticides will increase.