The correct answer is B) Threefold purchase. The threefold purchase is a type of tackle that consists of three parts or "falls" that run through a block, creating a mechanical advantage to lift or move heavy loads. This configuration is commonly used for tasks such as handling cargo, launching and recovering lifeboats, and other deck operations on vessels. The other options are incorrect because: Deck tackle refers to a more general term for lines and blocks used on the deck, while davit tackle is specifically for the lifting mechanism of a davit. Gin tackle is a different configuration using a single sheave block.