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
The drug in Norplant sub - dermal implant hormonal contraceptive is : 
Select and explain. 
A. Norethisterone, B. Norethynodrel, C. Medroxy - progesterone, D. Levonorgesterol
D: Levonorgesterol
Answer: D: Levonorgesterol 
Explanation: Levonorgesterol