Humayun, after being defeated by Sher Shah Suri took refuge in the court of

Safavid ruler of Iran

The correct answer is Option (2) → Safavid ruler of Iran

Humayun, the second ruler of the Mughal Empire, faced a significant setback when he was defeated by Sher Shah Suri in the Battle of Kannauj in 1540. Following this defeat, Humayun was forced into exile and sought refuge in various places before finding sanctuary in the court of the Safavid ruler of Iran, Shah Tahmasp. Humayun's decision to seek refuge in Iran was strategic, driven by the geopolitical dynamics of the time. The Safavids were a Shia Muslim dynasty, while the Mughals were Sunni. Despite these religious differences, the common threat posed by Sher Shah Suri, who was also Sunni, led to a diplomatic alliance between Humayun and Shah Tahmasp. The Safavid ruler welcomed Humayun and provided him with the military support needed to reclaim the Mughal throne. During his exile in the Safavid court, Humayun spent several years in Iran, gaining both political and military assistance. This period allowed him to regroup, plan his comeback, and strengthen his ties with regional rulers who could aid him in reclaiming his lost empire. Eventually, with the support of the Safavids and other allies, Humayun managed to recapture the Mughal throne in 1555, marking the restoration of the Mughal Empire in India.

So, the correct option is [2].