During the reign of which of the following Sultans of Delhi was actual power enjoyed by Balban ?

Option 3 : Nasiruddin Mahmud Shah 

The correct answer is Nasiruddin Mahmud Shah.

• During the reign of Nasiruddin Mahmud, who was made Sultan by Balban in exchange for the positions of Amiri-Hajib and Naib-i-mamlakat, Balban was awarded the position of Amiri-Hajib and Naib-i-mamlakat.
• He was also awarded a royal canopy by the sultan, indicating Balban's power during Nasiruddin's reign.
• Balban was one of Iltutmish's most efficient slaves.
• The Mongols sold him as a slave, and in 1232 AD, Iltutmish bought him and appointed him as Khassadar after being pleased by his accomplishments.
• During Razia's reign, Balban held the office of Amir-i-shikar, and successive sultans bestowed upon him the Jagir of Rewari and Hansi.

• Nasir ud din Mahmud Shah was the Mamluk Sultanate's seventh ruler (Slave dynasty).
• The court historian Minhaj-i-Siraj wrote the Tabaqat-i Nasiri, which is dedicated to him.
• Shamsuddin Iltutmish was his father (as clearly mentioned by Minhaj in Tabaqat-i-Nasiri).
• At the early age of 17 or 18, he succeeded to the throne of the Delhi Sultanate after the chiefs deposed Ala-ud-din Masud, believing Masud had become a tyrant.