Answer:
Harris's talent was whistling.
Step-by-step explanation:
Harris is wonderful at whistling. At first, holden has stopped wonderful painting his former prep school student with one single brush. Harris is the first person to annoy holden and still be able to earn his respect, this and not entering the museum are both positive signs that holden is entertaining more mature views. However, he is becoming more mature but he thinks it is weird.
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