The author concludes that most movie critics are wrong to believe that sentimentality detracts from aesthetic value.
Why? Because these critics draw this belief from the fact that sentimentality pervades so many movies that its absence makes a movie more interesting to people like themselves.
The author then compares this to concluding that a certain flavouring detracts from the quality of food if one usually has food that is prepared with a certain flavouring.
So, what is the flaw in reasoning here? The author concludes that the critics' belief is wrong because of the reason they came to hold this belief. The author does not address whether the critics' belief itself is correct; they are solely focused on the critics' reason fro holding this belief. This is restated by answer choice (D), making it our correct answer.
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