Final answer:
Coal fields matching up across continents is the evidence supporting the continental drift theory, as this shows that continents once shared the same environment and were connected.
Step-by-step explanation:
The explanation that provides support for the continental drift theory is that coal fields match up across continents. When Alfred Wegener proposed the idea of continental drift and the existence of a supercontinent called Pangaea, he presented several lines of evidence. One significant piece of evidence was the observation of similar types of coal fields on different continents, indicating that these continents were once connected and shared the same environment. This find complemented the jigsaw-like fit of the continents, the presence of similar fossils on widely separated lands, and matching geological features such as mountain ranges.
Mountains forming where Earth cooled and shrank do not directly support the continental drift theory since they do not demonstrate the movement of continents. Instead, the theory of plate tectonics explains mountain formation as a result of plates colliding or moving past each other.