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
The following primary tumours are common in the vulva except: 
Select and explain. 
A. Adenocarcinoma, B. Basal cell carcinoma, C. Choriocarcinoma, D. Squamous cell carcinoma
C: Choriocarcinoma
Answer: C: Choriocarcinoma 
Explanation: None