Answer
option (d) is the correct answer.
Work Step by Step
Option (d) is given that the climate change would affect the fitness of the grizzly bear population as climate change is lowering the food supply of the bears, which is likely to lower their ability to live or reproduce. The very low or freezing temperatures in the American northwest region during the winters is responsible for the reduction in the population of the mountain pine beetles. The freezing temperature causes the less availability of food to the bears, thereby reducing the ability of the bears to survive or even reproduce. Hence, option (d) is correct.
