This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: PCOD, hirsutism and galactorrhea, Subject name: Gynaecology & Obstetrics
A 28 years old lady is suspected to have polycystic ovarian disease. Sample for testing LH & FSH are best taken on the following days of menstrual cycle: 
Select and explain. 
A. 4-Jan, B. 10-Aug, C. 13-15, D. 24-26
A: 4-Jan
Answer: A: 4-Jan 
Explanation: In PCOS, determination of FSH and LH levels may help to confirm the diagnosis of polycystic ovaries.These are assayed on 2nd or 3rd day of the cycle.