What nerve is associated with the innervation of the anal canal?

The pudendal nerve is primarily responsible for the innervation of the anal canal. This nerve is a key player in sensory and motor functions related to the perineum, including the external anal sphincter, which is crucial for voluntary control over bowel movements. The pudendal nerve carries sensory information from the skin around the anal region and provides motor innervation to the muscles that support anal continence.

While the splanchnic nerves and the vagus nerve have roles in autonomic functions of the gastrointestinal system, they do not directly innervate the anal canal. The right phrenic nerve primarily innervates the diaphragm and is not involved in the innervation of the anal area. Therefore, the pudendal nerve is the correct answer due to its specific role in providing both sensory and motor innervation to the anal canal and its associated structures.