The correct answer is (C) To restrain (emotions, ambitions, etc.); to curb; to hold in; to bring under control; to control, as with a bridle. Also, to throw back one's head and draw chin in to show pride, anger, or scorn. Finally, to put a bridle (harness) on a horse.

Bridle comes from Middle English bridel, Old English bridlian.

Examples of use:

• It was essential to bridle her temper during the meeting.
• He bridled as soon as the subject was mentioned.