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
Clomiphene citrate used in initial treatment for most anovulatory infertile women is 
Select and explain. 
A. Steroidal triphenylethylene derivative, B. Given on 7th day to 10th day after onset of spontaneous menses, C. Can be administered if no follicle is >20mm and endometrium is <5mm, D. Is oestrogen antagonist only
C: Can be administered if no follicle is >20mm and endometrium is <5mm
Answer: C: Can be administered if no follicle is >20mm and endometrium is <5mm 
Explanation: Clomiphene citrate is non-steroidal derivative given on 3rd to 5th day of cycle. It has both oestrogen agoinst and antagonist properties.