This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ectopic Pregnancy (Hello ! Where are you ?), Subject name: Gynaecology & Obstetrics
Ectopic pregnancy is seen most commonly in: 
Select and explain. 
A. Previous H/O recurrent PID, B. Previous H/O aboion, C. Previous H/O twin pregnancy, D. Endometriosis
A: Previous H/O recurrent PID
Answer: A: Previous H/O recurrent PID 
Explanation: The most common cause of ectopic is Pelvic Inflammatory Diseases(PID).