The Dashavatara (10 avatars) of Lord Vishnu in order are: 1) Matsya (fish), 2) Kurma (tortoise), 3) Varaha (boar), 4) Narasimha, 5) Vamana, 6) Parashurama, 7) Rama, 8) Krishna, 9) Buddha, 10) Kalki. Therefore, the third avatar is Varaha (option C), making the claimed answer correct.