Ibn Battuta, the famous Moroccan explorer and traveler, visited the Delhi Sultanate during the reign of Muhammad bin Tughlaq. This is well-documented in his travel accounts and historical records. Muhammad bin Tughlaq ruled from 1325 to 1351, and his reign coincided with Ibn Battuta's visit to the Indian subcontinent. During his travels, Ibn Battuta served as a qadi (judge) in Muhammad bin Tughlaq's court, and his observations and experiences in the Delhi Sultanate are described in his travelogue "Rihla."

So, the correct option is [2].