Paul: Thanks for posting such nice questions. I've seen you answering
others questions. But, this is your chance to tease us
This is a hard questions.
Choices C, D and E are the contenters.
Choice D could be dropped because he took classes for two months and
two months is mostly enough time to get a feel about the college.
Choice E, There is no external factor affecting his learning. Either he is
not interested very much in learning or he may be musically disabled.
That leaves us with choice C.
Fingers crossed and waiting for Paul's teasing and educating reply.