This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal System, Subject name: Physiology
[{'content': 'Enterokinase acts in: \nSelect and explain. \nA. Stomach, B. Pancreas, C. Small intestine, D. Large intestine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Enteropeptidase (also called enterokinase) is an enzyme produced by cells of the duodenum and is involved in digestion in humans and other animals. Enteropeptidase conves trypsinogen (a zymogen) into its active form trypsin, resulting in the subsequent activation of pancreatic digestive enzymes. Absence of enteropeptidase results in intestinal digestion impairment.', 'role': 'assistant'}]