Answer:
b. Respect for persons
Explanation:
According to my research on different research methodology, I can say that based on the information provided within the question Humphreys study was an example of a violation of the principle of respect for persons. This is because the Tearoom Trade study was about homo-sexual relations in public places, and Humphrey pretended to be a lookout when instead he was just observing to gather data for his study. Therefore he violated the subjects trust and privacy by lying to them.
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