Question

A population of insects is sprayed with a new insecticide. Most of the
insects are killed but a few survive. In the next generation, many more of the
insects are unaffected by the insecticide. Which of the following BEST
explains these results?

Answer 1

Answer: This shows that over time, some insects can become "pesticide-resistant" meaning that pesticides don't affect them anymore. And this only happens every few generations. Therefore, each generation is being naturally selected and accumulating variations that make them resist the chemicals. This shows that each cockroach's genes are changing to give them variation from the rest of the population.

I hope this helps!