Which of the following is not one of South Asia's major rivers?

a. Brahmaputra

b. Ganges

c. Nile

d. Indus

Nile is not a River in South Asia!

It is the main river in Egypt, and it has provided irrigation for the crops and transport for ancient Egyptians, making their culture possible. Egypt is in Africa, not Asia, and definitely not in South Asia.

So the correct answer is C.