a joke that is a play on words is a\n○ riddle.\n○ comic.\n○ pun.\n○ prank.

Brief Explanations:

A pun is a form of word - play that exploits multiple meanings of a word, or of words that sound similar. A riddle is a question or statement intentionally phrased so as to require ingenuity in ascertaining its answer. A comic is related to humorous works like comic books. A prank is a practical joke.

Answer:

C. pun