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
All are used in treatment of infeility, except : 
Select and explain. 
A. Luteinizng hormone (LH), B. Prolactin, C. GnRH, D. Clomiphene
B: Prolactin
Answer: B: Prolactin 
Explanation: Prolactin