Final answer:
The pyloric sphincter opens into the small intestine (option C), which is where most digestion and nutrient absorption takes place. The cecum, part of the large intestine, is attached to the appendix.
Step-by-step explanation:
The pyloric sphincter opens into the small intestine. This valve regulates the flow of partially digested food, known as chyme, from the stomach into the duodenum, which is the first part of the small intestine. The small intestine is the site where the majority of digestion and absorption of nutrients occurs, with the bile produced by the liver playing a critical role in emulsifying fats allowing them to be more readily digested by enzymes. Once the food has been processed in the small intestine, undigested material then moves through the ileocecal valve into the large intestine or colon, where it is prepared for excretion.
The cecum is the part of the large intestine that attaches to the appendix. It is the starting point of the large intestine where the ileum of the small intestine connects through the ileocecal valve.