How did merchants of the Mauryan Empire use the Khyber Pass? A. to sail over oceans
B. to cross over valleys
C. to travel through deserts
D. to travel through mountains

b. to cross over valleys

Explanation:

The Khyber pass, was a mountain pass that's located in Pakistan. Many historians -predicted that This pass was started to be used as trade routes by the Kushan Empire. Prior to that, this pass only used for military's purposes.

After that, The Mauryan empire also start using Khyber pass as their trade routes. It allows their merchants to reach the market in middle east (mostly Pakistan or Afghanistan) at a much faster time compared to using the conventional roads.

answer:

it caused mass african migration, african populations to grow, african empires to topple, and racism against slaves to emerge.