This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunomodulators, Subject name: Pharmacology
Mechanism of action of Rituximab? 
Select and explain. 
A. Targets CD 20 antigen, B. Targets CD 52 antigen, C. Targets CD 22 antigen, D. Targets CD 38 antigen
A: Targets CD 20 antigen
Answer: A: Targets CD 20 antigen 
Explanation: Rituximab acts on CD 20 B cell antigen and useful in Hodgkins lymphomaRef: Sharma and Sharma 3rd ed/pg 874