What equipment is used as the painter while the liferaft is in the water?

The operating cord is the correct choice for the painter when the liferaft is in the water. The painter is an essential piece of equipment that helps to secure the liferaft to the vessel. It allows the liferaft to be towed or retrieved easily and is crucial for the safe operation of the liferaft. The operating cord is directly linked to the mechanism that activates the liferaft, ensuring that it is deployed correctly and functions as intended once in the water.

In contrast, a floating line typically serves different purposes, such as connecting items that need to float or providing a means for a swimmer to grab onto something while in the water. A hydrostatic release is designed to release the liferaft automatically when it reaches a certain depth in the water and is not used as a painter. Similarly, an anchor chain would be used for anchoring a vessel rather than for securing a liferaft after it has been deployed. Each of these options has its own specific role, but the operating cord uniquely serves the necessary function of securing and managing the liferaft.