Answer:
Step-by-step explanation:
A. The east coast of South America must have been attached to the east coast of Africa.
The Mesosaurus fossil is a freshwater reptile that existed during the early Permian period. The fact that its fossils have been found on both the east coast of South America and the east coast of Africa suggests that these continents were once connected. The presence of the same species on two different continents separated by an ocean provides strong evidence for the theory of continental drift, which suggests that the continents were once part of a single supercontinent called Pangaea, and have since moved apart over millions of years. Therefore, the correct answer is A.