What does the term "tack" encompass in horse training?

The term "tack" encompasses all equipment used on the horse, making the choice identifying this definition the correct answer. In the context of horse training and riding, tack includes a wide variety of items such as saddles, bridles, reins, stirrups, halters, and other accessories that enable the handler to ride, control, and care for the horse effectively.

Understanding the comprehensive nature of tack is essential, as each component serves a specific purpose in facilitating communication and control between the horse and rider, enhancing safety, and promoting optimal performance. By recognizing that "tack" refers not just to saddles, bridles, or any single piece of equipment but includes all necessary items used in the management and training of the horse, trainers and handlers can ensure they are fully prepared for any riding or training scenario.