30 points
this immense mountain range began to form between 40 and 50 million years ago, when two large landmasses, india and eurasia, driven by plate movement, collided. because both these continental landmasses have about the same density, one plate could not be subducted under the other. the pressure of the impinging plates could only be relieved by thrusting skyward, and forming the mountains.

a) eurasian
b) himalaya
c) rocky
d) ural