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
Failure of bleeding after withdrawal of oestrogen indicates : 
Select and explain. 
A. Uterine factor, B. Ovarian factors, C. Pituitary factor, D. Hypothalamic factor
A: Uterine factor
Answer: A: Uterine factor 
Explanation: Uterine factor