This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Gynaecology & Obstetrics
Which of the following ovarian tumor is most prone to undergo torsion during pregnancy : 
Select and explain. 
A. Serous cystadenoma, B. Mucinous cystadenoma, C. Dermoid cyst, D. Theca lutein cyst
C: Dermoid cyst
Answer: C: Dermoid cyst 
Explanation: "A benign cystic teratoma is the most common neoplasm to undergo torsion, and it to the M/C benign tumor diagnosed during pregnancy." A benign cystic teratoma is synonymous to dermoid cyst. REF : gynecology book of shaw 17th