The noun form of any verb is formed by suffixing either -ance or -ence to the verb. The noun form of the verb avenge is: vengeance. Correct answer is option C. The other options are incorrect as they do not follow the rule mentions above.
Options A and B are incorrect as the words-vengence and vengeance have incorrect spelling.
Option D is incorrect. To get the noun form of the verb-avenge, the letter a has to be dropped. But in this option, the letter a is retained. Hence, this answer is incorrect.