which would NOT be a compelling reason
for teaching music?
1. Musical intelligence is an aspect
2. Parents expect schools to teach
Wouldn't it be number 2?
There are cognitive and non cognitive aspects of intelligence. The compelling reason for developing certain aspects of the non-cognitive intelligence realm is that that aspect acts synergistically, or compliments, to develop the cognitive aspects.
Music, Art, emotional, social do relate to cognitive development.
Now to your question: Your use of "compelling" is interesting. What is compelling in one community is not compelling in another. Saying what is compelling, or a compelling reason is fraught with values and politics. Sex Education, religious instruction, art, music, and values education are all in these areas which differing folks say is "compelling" or not.
As for myself, I think that music and art should be taught in school, as my experience teaching math and science is that some kids need that expression, it helps develop them and complements their cognitive functioning. Not all kids, but some.
Your teacher is probably looking for a "textbook" answer here, which is in your text probably number 2. But in reality, and reality is where we live, what is compelling is much more complex.
Bobpursley is right. What is compelling in one community -- or even one family --can be markedly different from what's in another.
Personally, I would choose number 1, but that's primarily because I've read a lot of educational research, as well as Plato's Republic, which indicate good connections between music and math, or music and language development.
You'll have to check your text or your class notes.
I would definitely agree... music is a positive in developing math, coordination, language and many other aspect of mental development.
Whether parents "feel" it is important or not is not really relevant to its actual developmental importance.