This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Labour - normal, abnormal, malposition, malpresentation and their management, Subject name: Gynaecology & Obstetrics
Transverse diameter of the pelvic outlet is: 
Select and explain. 
A. 9.5 cm, B. 10.5 cm, C. 11.5 cm, D. 12.5 cm
B: 10.5 cm
Answer: B: 10.5 cm 
Explanation: Transverse diameter of the obstetrical outlet / inter-ischial tuberous diameter - 10.5 cm An inter-ischial tuberous diameter of 8 cm or less is defined as a Contracted Outlet