Which of the following is a fitness trade-off (compromise)?
a. Hummingbirds are the best pollinators of certain flowers, but bees are the best pollinators for orchids.
b. The strong, thick beak of a woodpecker helps it find insects in trees.
c. In some hornbill species, the male helps seal the female in a tree with her nest until the young are ready to fledge.
d. Turtle shells provide protection but are heavy and burdensome when moving.
Answer: D