Right Answer is: C
Loneliness means sadness because one has no friends or company.
Asceticism means severe self-discipline and avoiding of all forms of indulgence, typically for religious reasons.
Virtue means behaviour showing high moral standards.
As we can see that the correct word to be used in the sentence is “asceticism” because he lived in an abandoned place for years and only an ascetic can do it.
Hence, option C is the correct answer.