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: Gynaecology & Obstetrics
Shoest diameter is : 
Select and explain. 
A. Diagonal conjugate, B. Obstetric conjugate, C. True conjugate, D. All are equal
B: Obstetric conjugate
Answer: B: Obstetric conjugate 
Explanation: Obstetric conjugate