In the Second Battle of Tarain (AD 1192), it was Mohammad Ghauri who defeated Prithviraj. Option 4 is the correct answer. Prithviraj, who was a Rajput king and ruler of the Chauhan dynasty, faced invasion from Mohammad Ghauri, who was a powerful Muslim ruler from Afghanistan. Despite Prithviraj`s valiant efforts, Mohammad Ghauri emerged victorious in this battle. This marked a significant turning point in Indian history as it led to the establishment of Muslim rule in northern India. It is important to note that while options 1, 2, and 3 mention Prithviraj winning or defeating either Ghauri or Mahmud Ghazni, these options are incorrect.