The delhi sultanate lost control of northern indian when a period of disunity began after.
a. hindus in northern india rebelled against islamic rule
b. arab armies attacked to restore influence in india
c. armies of mongols and the successors of genghis khan invaded
d. european merchants took control of major port cities of india

They lost control of Northern India when some Hindus rebelled against Islamic rule which is governed by Muslims.Hindus and Muslims never get along well with each other because of religious and cultural differences.

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