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: Pathology
Direct coomb's test detects - 
Select and explain. 
A. Antigen in serum, B. Antibodies in RBC surface, C. Antigen in RBC surface, D. Antibodies in serum
B: Antibodies in RBC surface
Answer: B: Antibodies in RBC surface 
Explanation: None