Passage Summary: The author claims that because pianos make noise by hitting things with hammers, they belong in the percussion family, even though they have strings.

Conclusion: The piano is correctly categorized as a percussion instrument rather than a stringed instrument.

Reasoning: Musical instruments are classified based on the mechanical action used to produce sound, and a piano produces sound through the impact of hammers.

Analysis: To identify the conclusion, look for the 'claim' the author is trying to prove, which is signaled here by the word 'so.' The first sentence provides a general rule for classification, and the final sentence provides a factual description of how the piano operates. The middle sentence is the bridge that applies that rule to the specific case of the piano, making it the main point of the argument. Focus strictly on the structural relationship between these statements rather than evaluating if the musicologist is actually right about the piano.