A serene mind can never be the pioneer of a great revolution.

Answer: Option D

Serene : calm, peaceful, and untroubled; tranquil.
Nervous : easily agitated or alarmed.
Jocular : fond of or characterized by joking; humorous or playful.
Earnest : resulting from or showing sincere and intense conviction.
Agitated : feeling or appearing troubled or nervous.

Antonym of Serene is Agitated