Based on Darwin's ideas of descent with modification and natural selection, which observation would best support the idea that increased competition causes changes in a species?

A) A population of frogs develop greener skin after a hurricane blows away the white flowers in the environment

B) A population of artic foxes develop a brown fur color as warmer temperatures reduce the number of days of
snowfall in the area

C) A population of rattlesnake goes extinct as the water resources in their environment dry up during an
extreme, prolonged drought

D) A population of deer show an increase in antler size over time, which allows them to obtain more mates
during mating season