Final answer:
The best definition for "melancholy" is a feeling of pensive sadness with no apparent cause.
Step-by-step explanation:
The best definition for "melancholy" is option a) a feeling of pensive sadness with no apparent cause. Melancholy is often characterized by a deep and long-lasting sadness or a feeling of being downcast. It is different from temporary or situational sadness as it typically does not have an apparent cause and can persist for extended periods of time.
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