Answer;
-Natural selection;
Explanation;
-Natural selection is one of the basic mechanisms of evolution, along with mutation, migration, and genetic drift.
-Genetic diversity allows the different organisms to have different physiological characteristics. Some of them provides them with genetic resistance, others don’t. The ones which are resistant survive the pesticide, others don’t; this is called the natural selection. The ones which are resistant will live longer and have a larger offspring.
- From one generation to another, there will be more and more resistant pests (because of their larger offspring), and less and less unresistant pests (because they tend to die young). If the selection process goes on, someday the pesticide will be useless (it will kill no pest).