Scientists who search for fossils often use the term transitional fossil to describe some of their finds. An example of a transitional fossil is Dimetrodon, which lived 280-265 million years ago. Dimetrodon had a lizard-like appearance but had a sail-like structure sticking out from its back that allowed it to regulate its body temperature, an ability that is found today in modern warm-blooded mammals. While Dimetrodon swallowed its prey whole like reptiles do, it also had different types of teeth, a trait also common to mammals. Which of these statements best explains how transitional fossils support the theory of evolution?


A. Transitional fossils show traits common to ancestors as well as descendants.


B. Transitional fossils show how the organisms' characteristics remain the same over time.


C. Transitional fossils show how individual organisms can change their characteristics during their lifetimes.


D. Transitional fossils show how populations of past organisms were not able to change their characteristics over time.