What muscle controls the passage from the stomach to the lower gastrointestinal tract?

The muscle that controls the passage from the stomach to the lower gastrointestinal tract is the pylorus. This structure is located at the distal end of the stomach and consists of the pyloric sphincter, which regulates the flow of partially digested food (chyme) from the stomach into the duodenum, the first part of the small intestine. The pyloric sphincter functions to ensure that the chyme is released in a controlled manner, allowing for proper digestion and absorption of nutrients in the intestines.

The cardia refers to the area where the esophagus meets the stomach, but it does not regulate passage to the lower gastrointestinal tract. The duodenum is part of the lower gastrointestinal tract itself, where food continues to be digested, and the esophagus is the tube that carries food from the mouth to the stomach. Thus, the pylorus has the specific function of controlling the movement from the stomach to the duodenum, making it the correct answer.