This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Pathology
Which of the tumours are unique to pregnancy 
Select and explain. 
A. Luteoma, B. Serous cystadenoma, C. Mucinous cystadenoma, D. Teratoma
A: Luteoma
Answer: A: Luteoma 
Explanation: *Physiological proliferation of luteal cells in response to gonadotrophins in pregnancy - Theca lutein hyperplasia of pregnancy*Pathological proliferation of luteal cells in response to gonadotrophins in pregnancy- Luteoma . Luteoma is a type of sex cord stromal tumours( Ref: Robbins 8/e p1051)