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
The angle that tympanic membrane makes with the horizontal plane is ? 
Select and explain. 
A. 15deg, B. 25deg, C. 45deg, D. 55deg
C: 45deg
Answer: C: 45deg 
Explanation: Ans. is `c' i.e., 45degThe tympanic membrane slants downward and inward obliquely, so that it forms an angle of 30 - 45deg with the floor of horizontal canal.