Answer: The correct answer is -
D) have a mutation that allows them to survive treatment with medication.
Explanation -
Natural selection is a theory of evolution that was proposed by Charles's Darwin. According to this theory, organisms that have a beneficial gene variant (allele) to enhance their survival or that are capable of better adapting in their changing environmental conditions, will survive and produce large number of offsprings through reproduction.
Option D) in this question correctly correlates this theory as the mutation in the organism is enhancing its rate of survival.
Thus, option D) is the right answer.