A light sailing boat built especially for racing

Answer: Option C

One word substitute is Yacht.

Dinghy: a small inflatable rubber boat.
Canoe: a light, narrow boat with pointed ends and no keel, propelled with a paddle or paddles.
Yacht: a medium-sized sailing boat equipped for cruising or racing.
Frigate: a warship with a mixed armament, generally lighter than a destroyer (in the US navy, heavier) and of a kind originally introduced for convoy escort work.