The photograph at the right shows two penguins of the same species displaying different feather color patterns. The newly discovered all-black penguin had only black feathers since emerging from the egg. The sudden appearance of
this characteristic was most likely due to

A..an increase in sun exposure for the penguin chick
B. Deposition of oil on the feathers due to pollution
C. A random change in the sequences of bases in DNA
D. A change in the diet of the penguin chick