Answer:
Resistance develops because the weaker species die out. When an insect mutates or adapts a trait to defend against the insecticides, that can lead to nonrandom mating, which creates more of the species with a resistance. This is an example of natural selection because the weaker version of the species without the resistant genes will die from the insecticides more then the new version, leading to a new generation of insecticide resistant species.
Step-by-step explanation: