Animals like the firefly squid will migrate up and down the different layers of the ocean depending on the time of day. explain why?

The firefly squid, also known as the sparkling enope squid, as a member of the cephalopod family. These have photopores over their body, which emits lights making them the bio-luminescent life forms. These organisms live in the deep waters in the darkness during the day. But during the night, they come near the surface of the water, in search of the food. They attract the small fishes with their bio-luminescence, and then, catch them using their strong tentacles.

the answer is d.) homologous; have mammary glands