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
True about Brenner tumor:a) Usually bilateralb) Resembles fibromac) Accounts for 20% of all ovarian tumorsd) Common in postmenopausal age group 
Select and explain. 
A. c, B. bd, C. ab, D. ac
B: bd
Answer: B: bd 
Explanation: Brenner tumour is also called as Transitional cell tumour:
• It is a rare epithelial neoplasm of ovary resembling fibroma.
• It is an essentially benign tumour.
• Tumour is generally seen in women around menopause and is generally unilateral.
• Cause menopausal bleeding and Pseudomeig syndrome (ascites and hydrothorax).
• Malignant change is very rare.
• Histologically it shows walthard cell rests of transitional cellsQ, cells have coffee bean nuclei, cut section is gritty.