Answer: Option C
Solution(By Examveda Team)Fool :a person who acts unwisely or imprudently, a silly person.
Unhappy :not happy.
Disappointment :sadness or displeasure caused by the non-fulfillment of one's hopes or expectations.
Hardworking :tending to work with energy and commitment, diligent.
Diligent :having or showing care and conscientiousness in one's work or duties.
Synonym of Diligent is Hardworking.
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