6441. He whirled round in a trice, with a revolver in his hand.

✅ The correct answer is option C.
Circle : a round plane figure whose boundary (the circumference) consists of points equidistant from a fixed point (the centre).

Trifle : a thing of little value or importance.

Instant : prepared quickly and with little effort.

Hurry : move or act with great haste.

Trice : in a moment; very quickly.

Synonym of Trice is Instant