In the scenario you described, where foxes more easily catch mice with white fur, the likely consequence would be:
D) Brown fur will become predominant.
This is because the mice with white fur are more likely to be caught by predators (foxes), leading to lower survival rates and fewer opportunities to reproduce. As a result, over time, the population of mice will likely shift towards those with brown fur, which are better camouflaged and more likely to survive and reproduce.