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: Anatomy
[{'content': 'Constrictions in esophagus are present at distance of (from incisor) -a) 12 cmb) 25 cmc) 28 cmd) 36 cme)  40 cm \nSelect and explain. \nA. ac, B. Only b, C. be, D. ae', 'role': 'user'}, {'content': 'Answer: C \nExplanation: There are 4 esophageal constrictions. They are at 15cms, 22.5cms, 27.5cms and 37.5 to 40 cms, from the incisors.', 'role': 'assistant'}]