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
Which is not a mechanism of action of intra uterine contraceptive devices (IUCD)? 
Select and explain. 
A. Increased motility, B. Aseptic inflammation, C. Altered cervical mucus, D. Inhibit ovulation
D: Inhibit ovulation
Answer: D: Inhibit ovulation 
Explanation: IUCD acts as a foreign body in the uterus. It has no effect on ovulation.