What is the primary function of the standing part of a rope?

The primary function of the standing part of a rope is indeed to tie knots. The standing part refers to the length of rope that is not being used to form a knot or hitch and remains stationary. When tying knots, this portion acts as the anchor point that interacts with other parts of the rope to create various configurations. It is essential for creating secure knots that can hold or support loads effectively.

While the other choices touch on important uses of rope, they do not accurately capture the main role of the standing part. For instance, lifting loads typically involves utilizing the running end or other sections of the rope, but the standing part itself serves as the base for tying those essential knots that enable effective lifting techniques. Similarly, attaching to rigging involves both the standing and running parts, but it's the standing part that specifically supports knot formation. Stability is a byproduct of how well knots secure loads, rather than a direct function of the standing part itself.