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
Drugs used for ovulation induction are:a) Gn RHb) Clomiphene citratec) Gonadotropinsd) Letrozolee) Danazol 
Select and explain. 
A. bcd, B. acd, C. ac, D. bd
A: bcd
Answer: A: bcd 
Explanation: Most commonly used drugs for ovulation induction:
1. Clomiphene citrate (CC)
2. Letrozole
3. Gonadotropins