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
Diagonal conjugate is defined as the distance between : 
Select and explain. 
A. Upper border of symphysis pubis and the sacral Promontory, B. Lower border of symphysis pubis and the sacral Promontory, C. Lower border of symphysis pubis and the third piece of sacrum, D. Lower border of symphysis pubis and tip of sacrum
B: Lower border of symphysis pubis and the sacral Promontory
Answer: B: Lower border of symphysis pubis and the sacral Promontory 
Explanation: Lower border of symphysis pubis and the sacral Promontory