Which nerve provides parasympathetic innervation to the stomach?

The vagus nerve is indeed responsible for providing parasympathetic innervation to the stomach. This nerve, also known as cranial nerve X, plays a critical role in the autonomic regulation of the digestive system. It provides fibers that synapse in the wall of the stomach and stimulate digestive functions such as increasing gastric secretions and promoting peristalsis, which aids in the movement of food through the gastrointestinal tract.

The vagus nerve originates in the brainstem and has extensive pathways that influence various organs, including the heart, lungs, and digestive tract. Its action in the stomach enhances motility and supports the digestive processes, allowing for efficient breakdown and absorption of nutrients.

Other nerves mentioned do not provide parasympathetic innervation to the stomach. The thoracic splanchnic nerve mainly transmits sympathetic fibers, and the pelvic splanchnic nerve innervates structures in the lower part of the body rather than the stomach. The phrenic nerve is responsible for diaphragm innervation and does not play a role in the autonomic control of the stomach. Therefore, the vagus nerve is the correct choice as it is the primary parasympathetic nerve influencing stomach function.