The correct answer is (A) A woman's (close-fitting) dress. Also, a scabbard for a knife or sword; a similar close-fitting case or protective covering for the blade of a dagger or similar weapon, or a tool.

Sheath comes from Old English sc?th, Dutch scheede, German scheide.

Examples of use:

• She selected a bright green sheath to wear to the party.
• He carefully eased his sword back into its sheath.