What is indicated by a hairline in Dutch rabbits?

The appearance of a hairline in Dutch rabbits specifically refers to the connection between the blaze and the collar. In Dutch rabbits, the coat pattern is characterized by a distinct facial blaze and a collar around the neck area. A hairline indicates that these two elements—the blaze and the collar—are well-defined and seamlessly join together, which is a characteristic trait of the breed. This feature is important in visual standards for show rabbits, as it contributes to the overall aesthetic and conformity to breed standards.

The other options do not accurately represent the significance of a hairline in Dutch rabbits. For example, markings on the tail or features of the hindquarters relate to different aspects of the rabbit's appearance and do not connect to the specifics of the hairline. Additionally, a signal of age does not relate to this trait in the context of Dutch rabbits. Understanding the significance of the hairline helps in visual identification and judging of Dutch rabbits in competitive settings.