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
True about tubal pregnancy : 
Select and explain. 
A. IUCD predisposes, B. Prior tubal pregnancy, C. Prior h/o PID/Chlamydia infection, D. All
D: All
Answer: D: All 
Explanation: All