In traditional sailing ships, which knots were used at the top of the masts?

The correct answer identifies the knot used specifically at the top of masts on traditional sailing ships. The mast head knot, often simply referred to as the mast head, is crucial because it secures rigging and provides stability to the mast. This specific knot is designed to accommodate the unique stresses and loads that mast tops experience, such as wind tension and sail movements.

The other knots listed serve different purposes. For instance, the bale sling is utilized for lifting loads, while the timber hitch is primarily used for securing logs or timber to a line. The sheepshank is typically employed to shorten a length of rope, which is not relevant at the mast head. Understanding the applications and functionalities of each knot helps clarify why the mast head knot is the correct choice for securing rigging at the ship's mast top.