Question

multiple choice question the first mammals were small and arose during the cambrian period. permian period. paleogene period. jurassic period.

Explanation:

The first mammals appeared during the Jurassic period. The Cambrian period is known for the Cambrian explosion of invertebrate life. The Permian period ended with a mass - extinction event. The Paleogene period came after the extinction of the dinosaurs and saw the diversification of mammals, but not their origin.

Answer:

D. Jurassic period