Fact 1: Some birds are pollinators that co-evolved with plants. Fact 2: Hummingbirds are the most common bird pollinators. Given the two facts above, hummingbirds are what they are today as a necessary consequence of their relationship to what?

Select from the following. A). a feeder. B). humans. C). bees. D). survival. E). animals. F). Plants. G). Earth. H). weeds.
Answer:
F).