What line is used to hold the ship to the pier?

The line used to hold the ship to the pier is the mooring line. Mooring lines are essential for securing a vessel alongside a wharf or dock, providing stability and preventing movement caused by currents, wind, or waves. These lines are typically made of strong materials to withstand the forces acting on the ship and ensure it remains safely moored.

Spring lines, while they play a crucial role in maneuvering a vessel in tight quarters, are primarily used to control the forward and backward movement of the ship alongside the pier, rather than for securing it in place. Bowlines and sheet lines are specific types of knots or lines used in sailing and rigging but do not serve the purpose of holding a ship to a pier directly. Thus, the mooring line is the correct and most relevant choice for this specific function.