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: Radiology
Ectopic pregnacny, characteristic finding in USG is: 
Select and explain. 
A. Absence of gestational sac in uterus, B. Complex adenexal mass, C. Resistance in coloured Doppler, D. Free fluid in peritoneal cavity
A: Absence of gestational sac in uterus
Answer: A: Absence of gestational sac in uterus 
Explanation: A i.e. Absence of gestational sac in uterus Best method of diagnosing unruptured ectopic pregnancy is combination of transvaginal sonography & quantitative B-HCG valuesQ.