What is a "cap" in the context of rabbit markings?

In the context of rabbit markings, a "cap" refers specifically to the line where the lower ear color meets the head color. This feature is important in identifying certain breeds and variations of rabbits, as it can denote specific genetic traits and overall conformation standards for different types of rabbits. Recognizing the cap helps breeders and judges evaluate rabbits during competitions, particularly regarding breed standards where color and markings are critical.

The other choices do not accurately define what a "cap" is. Eye markings, belly patterns, and tail features pertain to different aspects of a rabbit's appearance but are not related to the "cap" marking specifically. Understanding the significance of the cap provides insight into rabbit judging and breeding practices, enhancing a rabbit owner's ability to assess and appreciate the aesthetics and characteristics of their rabbits.