What piece of equipment is advisable for a horse to wear for added control during leading?

The most suitable equipment for added control when leading a horse is the bridle. A bridle consists of a headpiece that holds a bit in the horse's mouth and is used primarily for riding or driving. When leading a horse, using a bridle provides a degree of control that may be necessary in certain situations, particularly with highly spirited or strong animals. It allows the handler to have a direct influence over the horse's head and mouth, which can help in managing the horse’s movements more effectively.

On the other hand, while halters and head collars are commonly used for leading, they might not offer the same level of control as a bridle, especially if the horse is acting up or needs more precise handling. Saddles, however, are not applicable for leading; they are essential for riding but do not serve a purpose in the context of leading the horse.