This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Which of the following is a reflex mediated by vagus? 
Select and explain. 
A. Bile flow from liver, B. Pancreatic secretion of bicarbonate, C. Cephalic phase of gastric secretion, D. Mucous secretion from the Brunner's glands
C: Cephalic phase of gastric secretion
Answer: C: Cephalic phase of gastric secretion 
Explanation: None