What is the rule of thumb for how far to pay out the sea anchor?

The correct approach to determining how far to pay out a sea anchor is based on the distance between wave crests, as it allows for effective stabilization of the vessel in rough seas. The guideline of using a range from one-fourth to three-fourths of the wave crest distance is particularly relevant, as this range helps to ensure that the vessel is adequately restrained without being too tightly tethered, which could lead to capsizing or other navigational hazards.

When properly deployed, a sea anchor reduces drift while maintaining the bow's orientation into the waves, minimizing the impact of dynamic forces acting on the vessel. Using the recommended distance also aids in reducing the strain on both the anchor and the boat itself, promoting safety and stability.

While the other responses provide various theoretical guidelines, they do not align as closely with standard maritime practices related to wave dynamics and vessel stabilization. Thus, the choice of one-fourth to three-fourths of the distance between wave crests effectively balances safety and functionality in potentially hazardous conditions at sea.