What is a defining feature of static ropes?

Static ropes are characterized by their low stretch properties, which is an essential feature for activities requiring stability and control, such as rescue operations or rappelling. Specifically, a defining feature is that static ropes typically have less than 6% elongation when a load of 10% of the rope's breaking strength is applied. This minimal elongation factor allows for precise movements and the ability to maintain the position of equipment, making static ropes ideal for applications where stretching might be dangerous or undesirable.

The other options describe features that do not align with the purpose and characteristics of static ropes. For example, a significant percentage of stretch, like over 20%, would be more characteristic of dynamic ropes designed for absorbing energy during falls. Additionally, while static ropes can be used for various climbing activities, lead climbing typically relies on dynamic ropes to handle the forces involved when a climber falls. The mention of long-distance running introduces a context unrelated to rope rescue, as it does not pertain to the functional use of static ropes in the realm of climbing or rescue operations. Thus, the correct answer reflects the defining characteristic that sets static ropes apart from other rope types.