Which of the following traits evolved multiple times over the course of the evolution of vertebrates?

a. Hair

b. Flight

c. Oviparity

d. Homodonty

The correct answer is option b, that is, flight.

Explanation:

Our atmosphere is comparatively thick, and it possesses the tendency of supporting the creatures, which are light. The factual flight, however, relies upon the fact that whether an individual is sufficiently light, and is equipped with appropriate characteristics, and has a desire to make a since the attempt to make aloft.

The birds are the most apparent fliers in the world we live in. The first bird appeared in the fossil about sixty-five million years ago. Like birds, bats also have developed an elegant approach to flight. Similarly to birds, they exhibit lightweight and slender bones, and a compact skeleton, and have developed strong muscles for flapping flight.