Final answer:
The resistance to pesticides in the insect offspring illustrates the process of natural selection, where environmental pressures favor inherited traits that confer a survival advantage.
Step-by-step explanation:
The process illustrated by the offspring of the insects that were resistant to pesticides is natural selection. In this scenario, a farmer used a pesticide, which created a selective pressure, and the insects that survived had a trait that provided resistance to the pesticide. These surviving insects subsequently reproduced, passing on their resistant traits to their offspring.
As a result, the population of insects evolved over time to become predominantly resistant to the pesticide. This is a modern example of natural selection, akin to a process that Charles Darwin described, wherein environmental pressures, rather than human choices, determine which traits are favored in successive generations. In contrast, selective breeding is an artificial process where humans intentionally choose specific traits, whereas natural selection is a natural process.