The correct answer is (C) A two-masted vessel, which has the shorter mast nearer the stern; a sailing vessel that is rigged fore and aft on two masts, with the larger main mast forward and the mizzen mast stepped forward of the rudder. The mizzenmast is stepped further forward than in a yawl.

Ketch comes from Middle English cache.

Examples of use:

• His dream had been to sail own his own ketch around the world.
• He keeps his ketch in The Bahamas, although he has no home there.