The child had learned music by ear, he had never even seen it what?
Options:
- opera
- written on paper
- composed
- teacher
- stolen Hmmm, let me think.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Something written on paper can be seen. Music can be written on paper.
So, the answer is written on paper.