Choose a word similar to the group: Calm, Peaceful, Tranquil.

C. SERENE

Choose a word similar to the group: 'ancient, old, archaic'.

C. OUTDATED

Choose a word similar to the group: Happy, Joyful, Cheerful.

C. ELATED

Choose a word similar to the group: Strong, Sturdy, Robust.

C. POWERFUL

Choose a word similar to the group: Calm, Peaceful, Tranquil.

C. SERENE