Answer:
c.mountain ranges
Explanation:
scientists wondered how they where formed and came to the conclusion that they might be forced upward by movement of the earths crust
Answer:
mountain ranges
Explanation:
The world's tallest mountain ranges form when pieces of Earth's crust—called plates—smash against each other in a process called plate tectonics, and buckle up like the hood of a car in a head-on collision.