Answer:
C. Afghanistan
Step-by-step explanation:
"Hindu Kush" is a mountainous area that can be found in Afghanistan. During ancient times, it became a major area for the expansion of Buddhism. This is the reason why you can see Buddhist-inspired places such as the "The Buddhas of Bamiyan." However, this religion was replaced by Islam.
The area also became a notable dividing mark which separated Russian areas from British areas.