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
A 28 years old female with a history of 8 wks amenorrhoea complains of vaginal bleeding and lower abdominal pain. On USG examination there is gestational sac with absent fetal pas. The diagnosis is : 
Select and explain. 
A. Ectopic pregnancy, B. Incarcerated aboion, C. Threatened aboion, D. Corpus luteum cyst
B: Incarcerated aboion
Answer: B: Incarcerated aboion 
Explanation: Ans. is b i.e. Incarcerated aboion