The perceptual process is affecting Paul is horn effect.
Horn effect can be defined as way in which a person tend to judge another person based on the negative characteristic the person possess which in turn affects the decisions as well as judgments they make.
Hence, Paul has horn effect personality which is why he thinks that the Professor is a poor instructor and finds her class too challenging.
Learn more about Horn effect here:https://brainly.com/question/988504
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