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
Which causes torsion of ovarian tumor : 
Select and explain. 
A. Trauma, B. Uterine contraction, C. Physical movements, D. All
A: Trauma
Answer: A: Trauma 
Explanation: Trauma