Which of the following describes a horse with a steep neck?

A horse with a steep neck is characterized by an upright neck positioning. This means that the neck is held more vertically rather than at a more relaxed or horizontal angle. An upright neck can indicate tension in the horse and may affect the overall balance and movement of the horse. It may also affect how the horse carries itself and can influence its performance capabilities.

The other descriptors do not accurately capture the features of a horse with a steep neck. For instance, an elegant neck is typically more arched and graceful, while a stout neck would imply strength and thickness, which may not align with the characteristics of a steep neckline. Similarly, a long neck usually indicates a more horizontal line and an overall more extended appearance, which contrasts with the notion of steepness. Therefore, describing a horse with a steep neck is best suited by the term upright.