@knoxygirl the easiest way to distinguish between a main conclusion and a subsidiary conclusion is to ask yourself which one supports the other.
The main conclusion will not support whereas the subsidiary conclusion will support the main conclusion.
So let's take a look at these two conclusions here and use this test:
Conclusion 1: "The reason music with a simple recurring rhythm exerts a strong primordial appeal is that it reminds us of the womb environment."
Conclusion 2: "Thus it is extremely natural that in seeking sensations of warmth and security throughout life, people would be strongly drawn toward simple recurring rhythmic sounds."
Notice here that Conclusion 2 supports Conclusion 1, so Conclusion 2 is our subsidiary conclusion and Conclusion 1 is our main conclusion.
Hope that helps! Please let us know if you have any other questions.
