Which of the following is NOT considered a disobedience?

The correct choice relates to the definition and classification of disobediences in equine disciplines, particularly in jumping and eventing. A knockdown refers to a situation where a horse knocks a rail off a jump due to its effort to clear it, indicating an attempt to perform the jump rather than a failure to obey. This is a different scenario than disobediences, where the horse actively avoids the jump or stops in front of it.

In contrast, a refusal, run out, and stopping at a fence are all instances where the horse does not comply with the rider's intent to jump. A refusal occurs when the horse halts before a jump, a run out happens when the horse evades the jump entirely by moving to the side, and stopping at a fence reflects the horse's decision to not attempt the jump at all. These behaviors indicate a lack of obedience and willingness to jump, making them clear examples of disobedience in competitive settings.