Why Have Parts of South and Central Asia Become So

Why have parts of South and Central Asia become so important that they cause nations to fight over them?

A) Vital trade routes between West and East run through South and Central Asia.
B) China and India have become so overpopulated that they need more land.
C) Valuable natural resources such as gold have been found in extraordinarily high quantities in those countries.
D) A large portion of the world's greatest philosophers in modern history have come from these countries. They offer significant educational opportunities.