Final answer:
The Rocky Mountains (B) were formed by volcanic activity and large-scale earth movements during the Laramide Orogeny in the Late Mesozoic and Early Cenozoic periods.
Step-by-step explanation:
The correct answer to the question is B. Rocky Mountains. The Rocky Mountains were primarily formed from large-scale earth movements and volcanic activity. During the Laramide Orogeny, which took place during the Late Mesozoic and Early Cenozoic eras, the Rocky Mountains underwent significant changes due to tectonic activities. The process involved low-angle subduction, which led to deformation in the overlying plate and ultimately the creation of the mountain range we see today. Unlike the mountain ranges formed by Continent-Continent convergent boundaries, such as the Himalayas, the Rockies were the result of different tectonic processes. Since their initial formation, the Rockies have been subjected to glaciation and erosion, which have sculpted their peaks and landscape.