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
While putting nasogastric tube, the length is measured from upper incisors. What is the distance from upper incisors to cardia of the stomach? 
Select and explain. 
A. 15 cm, B. 25 cm, C. 40 cm, D. 60 cm
C: 40 cm
Answer: C: 40 cm 
Explanation: The esophagus is about 25 cm (10 in.) long. The distance from the upper incisor teeth to the beginning of the esophagus (cricoid cailage) is about 15 cm (6 in.); from the upper incisors to the level of the bronchi, 22 to 23 cm (9 in.); and to the cardia, 40 cm (16 in.).