Theorist: Hatred and anger, grief and despair, love and joy are pairs of emotions that consist of the same core feeling and are distinguishable from each other only in terms of the social conditions that cause them and the behavior they in turn cause.
Conclusion (so)
Even if the meaning of a given piece of music is the emotion it elicits, this can mean only that music produces the core of a given emotion.
Evidence (for)
There are pairs of emotions that have the same core feeling, but can be distinguished from each other only in terms of the social conditions that cause them or the behavior they cause.
Intermediate Conclusion (therefore)
Music by itself cannot create social conditions or cause human behavior.
Evidence
Music is merely sound.
Evaluate
Whenever we do Role and Main Conclusion questions, we expect that 90% of the time the Main Conclusion will appear earlier than at least some of its support.
The word "So" attached to the first claim of the 2nd sentence indicates that the 1st sentence is supporting the "So" claim. Thus, the main conclusion can't possibly be the first sentence.
The word "for" (FABS: for, after all, because since) indicates support, so we know that the final two claims are there to support the "So" claim that begins the 2nd sentence.
Whenever we see a structure like this: X is true. After all, Y is true and thus Z is true.
We know that X was the main conclusion, and that the 2nd sentence serves to support X. The "thus" within the 2nd sentence tells us that Y supports Z.
Similarly, the "therefore" in the final sentence tells us that "music is merely sound" supports .
Goal
They're asking us about the claim that "music is merely sound", which supports an intermediate conclusion, which then supports the main conclusion.