Tughril Khan raised a standard of revolt during whose reign?

Explanation

An important revolt during Balban’s reign was the revolt of Tughril Khan. Balban had appointed Tughril Khan as the governor of Bengal, but he declared himself the independent ruler of Bengal, assumed the title of “Sultan Mugisuddin,” issued coins in his own name, and also had the khutba read in his name. To suppress Tughril’s revolt, Balban first sent an army under Amin Khan and thereafter under Bahadur, but both failed. Enraged, Balban advanced towards Bengal along with his son Bughra Khan, but Tughril fled after abandoning his capital. Ultimately, Tughril was captured and killed, and Balban appointed his son Bughra Khan as the iqtadar of Bengal.