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: Pharmacology
Ofatumumab is a monoclonal antibody against : 
Select and explain. 
A. CD19, B. CD79a, C. CD20, D. CD25
C: CD20
Answer: C: CD20 
Explanation: Ofatumumab is a monoclonal antibody against CD20 used in the treatment of SLE.