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
Gemtuzumab ozogamycin is a monoclonal antibody against 
Select and explain. 
A. CD 30, B. CD 33, C. CD 45, D. CD 79a
B: CD 33
Answer: B: CD 33 
Explanation: It is a monoclonal antibody against CD33, used for CD33+ve AML.