Which of the following examples of an ecological effect leading to an evolutionary effect is most correct?

A) When seeds are not plentiful, trees produce more seeds.
B) A few organisms of a larger population survive a drought and then these survivors emigrate to less arid environments.
C) A few individuals with denser fur survive the coldest days of an ice age, and the reproducing survivors of the ice age all have long fur.
D) Fish that swim the fastest in running water catch the most prey and more easily escape predation.
E) The insects that spend the most time exposed to sunlight have the most mutations.