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 acts against : 
Select and explain. 
A. CD11a, B. CD22, C. CD33, D. CD45
C: CD33
Answer: C: CD33 
Explanation: Gemtuzumab used in the treatment of AML, is a monoclonal antibody against CD33.