If you were investigating why the thumbs-up and the "okay" hand signals used in North America are considered rude gestures in certain other cultures, you would be engaging in the study of what?

You would be engaging in the study of kinesics.

Explanation:

Kinesics is the study of how communication takes place non-verbally through gestures, facial expressions, and body movements. If you were, therefore, to study why the "okay" hand signal used in North America is rude in Brazil, for instance, you would be engaging in the study of kinesics. You would be studying a gesture, a non-verbal form of communication, and the meaning it conveys in different cultures.

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