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
[{'content': 'What is the common cause of labial fusion in an adult female? \nSelect and explain. \nA. Congenital adrenal hyperplasia, B. Fetal exogenous androgen exposure, C. Abdominal wall defects, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Labial fusion in adult women is most commonly due to classical congenital adrenal hyperplasia. Other causes include, Fetal exogenous androgen exposure Abdominal wall defects Ref: (2010). Chapter 40. Reproductive Tract Abnormalities. In Cunningham F, Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (Eds), Williams Obstetrics, 23e.', 'role': 'assistant'}]