<span>The situation is one similar to the development of antibiotic resistance. The initial five years of spraying wiped out most of the pests; however, the killing also helped the pesticide-resistant pests to survive and thrive since they had less competition. Over the period of five years, the pesticide resistance became more and more common among the beetles and in the eighth year, almost all of the beetles were resistant to the pesticide. Thus, the answer is D.</span>
This is because these characteristics normally have a low survival value for the species. Natural selection is a process that causes heritable traits that are helpful for survival and reproduction to become more common, and more harmful traits to become rare. This occurs because organisms with advantageous traits pass on more of these heritable traits to the next generation.
There are guard cells surrounding each stoma that cause them to open or close throughout the life cycle of the plant. This occurs in response to water and ions concentration in the plant cell.