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
Mechanism of action of combination OCPs in treatment of AUB - E 
Select and explain. 
A. Diminshed prostaglandin synthesis., B. Decreased endometrial fibrinolysis., C. Endometrial atrophy., D. All of the above.
D: All of the above.
Answer: D: All of the above. 
Explanation: Combined OCPs have all the actions mentioned.