The correct answer is B) chocks. Fairleads and chocks both serve the same function of guiding and directing lines, cables, or ropes on a vessel. Fairleads are fixed structures with an opening or hole that lines pass through, while chocks are similar structures that lines are passed over. Both help prevent lines from becoming fouled or damaged by controlling their direction and preventing them from rubbing against the vessel's structure. The other options are incorrect because bollards, bitts, and deadeyes have different functions - bollards and bitts are used for securing or mooring lines, while deadeyes are used in the standing rigging of a sailing vessel.