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
At what level of b-HCG is it that normal pregnancy can be earliest detected by TVS : 
Select and explain. 
A. 500 IU/m1, B. 1000 IU/ml, C. 1500 IU/ml, D. 2000 IU/ml
B: 1000 IU/ml
Answer: B: 1000 IU/ml 
Explanation: None