Birds' feet change slowly over time, depending on their habitat. Ptarmigans live in snowy areas and eat pine needles, twigs, and insects. Roadrunners live in deserts and plains and eat anything they can catch. Peregrine falcons live on high perches and use their talons for grasping their prey. Mallards live near water and swim and dive for food. What is an inherited behavior or physical change that helps an organism survive and reproduce in its environment?

A. adaptation
B. variation
C. evolution
D. species