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: Ophthalmology
A blow out fracture of orbit refers to a fracture in: 
Select and explain. 
A. Roof of the orbit, B. Posterior wall of floor of orbit, C. Medial wall of orbit, D. Medial pa of floor of orbit
D: Medial pa of floor of orbit
Answer: D: Medial pa of floor of orbit 
Explanation: Medial pa of floor of orbit