Based on physical observations, which is the most direct evidence that the Appalachian Mountains are probably older than the Rocky Mountains? A. The Appalachians are at a lower elevation than the Rockies are.
B. The Appalachians have a larger mineral deposit concentration than the Rockies.
C. The Appalachians are on the East Coast, while the Rockies are on the West Coast.
D. The Appalachians are smooth and rounded while the Rockies have sharp and jagged edges