Which geographical feature most affected the level of early civilization in India?

Question

Which geographical feature most affected the level of early civilization in India?

Answer 1

The rivers of the Indus River valley. It made the land fertile and provided transportation.

Answer 2

Earthquakes...

Which led to tsunamis & flooding...This fault zone led to the repeated destruction of the Mohenjo-Daro & Harappan civilizations, even though the Indus River Valley appeared to be an initially promising location for settlements...

Also, the fact that the Himalyas virtually surround Northern India, while the Indian Ocean surrounds the Indian sub-continent to the south, resulting in somewhat of a confinement of migration possibilities...