Scientists believe that a major factor promoting the adaptive radiation of mammals was probably
A. their development of fur.
B. the mass extinction of most dinosaurs, an event that opened up new ecological opportunities.
C. internal fertilization.
D. the origin and diversification of flowering plants.
Answer:B
Scientists believe that a major factor promoting the adaptive radiation of mammals was probably
A. their development of fur. B. the mass extinction of most dinosaurs, an event that opened up new ecological opportunities. C. internal fertilization. D. the origin and diversification of flowering plants.