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
A 56 year old women presents with post-menopausal bleeding. Her Transvaginal scan shows endometrial thickness of 8mm. Endometrial biopsy shows moderately differentiated adenocarcinoma cells. Which of the following is most appropriate staging investigation 
Select and explain. 
A. CT - Scan of Pelvis, B. Chest X-ray, C. MRI scan of Pelvis, D. Hysterosalpingography
C: MRI scan of Pelvis
Answer: C: MRI scan of Pelvis 
Explanation: MRI scan is used to determine extent of tumor for staging, so as to plan surgery