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
Child with primary amenorrhea with negative progesterone challenge test but positive combined progesterone and estrogen test. Diagnosis may be: 
Select and explain. 
A. Mullerian agenesis, B. PCOD, C. Asherman syndrome, D. Prolactinoma
D: Prolactinoma
Answer: D: Prolactinoma 
Explanation: This child is presenting with primary amenorrhea with:
• Negative progesterone challenge test - which rules out PCOD (which may sometimes manifest as primary amenorrhea)
• When next step was done i.e., estrogen, progesterone combined test - It comes out to be positive i.e., compartment I system (uterus, endometrium and outflow tract) is normal if properly stimulated by estrogen which rules out mullerian agenesis and Ashermann’s syndrome.
• Positive estrogen progesterone combined test means the defect is in the production of estrogen i.e., either ovaries, pituitary, or hypothalamus.
So from the given options we have to look for a cause which involves either of the above sites, which in this case is prolactinoma.