Answer:
C. search for a gold mine.
Explanation:
The main character of the " The call of the wild" is a domestic dog "Busk". Who lived with different masters through out his life as mentioned in the story. Once Thornton who was a gold hunter saved this dog from a cruel master, and the dog became emotionally attached with Thornton and stays with him until he got killed. He often takes the dog along with him on his gold hunting missions.