In a certain area, mosquitoes that can resist the effects of pesticides (insect-killing chemicals) now exist in greater numbers than10 years ago. What is the most probable explanation for this increase in numbers?
Select one:
Mosquito eggs were most likely to have been fertilized when exposed to the pesticides.
The pesticides acted as a repoductive hormone for previous generations of mosquitoes.
The pesticides serve as a new source of nutrition.
Genetic differences permitted some mosquitoes to survive the use of the pesticides.