Which of the following describes a virus? A. A virus does not have a cell wall, nucleus, and eats.

B. A virus has a cell, a nucleus, and does not eat.

C. A virus does not eat, use energy, or have cells.

D. A virus does not have a cell, produces carbon dioxide, and uses oxygen.

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .