Which of the following helps prevent horses from damaging fences?

An electric fence is an effective solution for preventing horses from damaging fences due to its deterrent nature. Horses are intelligent animals, and they quickly learn to associate the mild shock from an electric fence with an unpleasant experience, which discourages them from attempting to push against or lean on the fence. This not only helps maintain the integrity of the fence itself but also prevents potential injuries to the horses.

Wooden fences, while sturdy, can still be damaged if horses lean on or chew the wood. Barbed wire is not recommended for horses as it poses the risk of injury. Chain link fences, although durable, do not provide the same deterrent effect as an electric fence and can also allow horses to reach through and potentially damage their mouths or cause injury. Thus, the electric fence stands out as the most effective option for protecting both the fence and the horses.