This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc. (R.B.C), Subject name: Pathology
Routine Rh typing includes testing? 
Select and explain. 
A. A antigen, B. B antigen, C. C antigen, D. D antigen
D: D antigen
Answer: D: D antigen 
Explanation: Ans. is 'd' i.e., D antigen o After ABO, the most important antigen in transfusion practice is D. The D antigen is a member of the Rh system.