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
Following are associated with high risk of ovarian cancer except 
Select and explain. 
A. Endometriosis, B. Smoking, C. Obesity, D. Multiparity
D: Multiparity
Answer: D: Multiparity 
Explanation: Nulliparity is a risk factor for ovarian cancer.