How have finches on the Galápagos Islands adapted to fill specific niches? A. Each species of finch has a beak designed for a different food source
B. All species have average beaks that can access the same food sources
C. one species of finch evolved the optimal beak design and can eat any food source
D. all species of finches have average beaks, but they instinctively only try to eat one type of food