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: ENT
Otosclerosis typically begins at: 
Select and explain. 
A. Scutum, B. Round window, C. Tympanic membrane, D. Fossa antefenestrum
D: Fossa antefenestrum
Answer: D: Fossa antefenestrum 
Explanation: Fossa antefenestrum