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: Anatomy
Vaginal sphincter is formed by all except: 
Select and explain. 
A. Internal urethral sphincter, B. External urethral sphincter, C. Pubovaginalis, D. Pubovaginalis
A: Internal urethral sphincter
Answer: A: Internal urethral sphincter 
Explanation: A i.e. Internal urethral sphincter The musculature surrounding the internal urethral orifice of female bladder is not organized into an internal sphincter. In other words females lack internal urethral sphincterQ