This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Targeted Anticancer Drugs and Immunosuppressants, Subject name: Pharmacology
Which of the following monoclonal antibodies is a humanized antibody? 
Select and explain. 
A. Rituximab, B. Palivizumab, C. Infliximab, D. Basiliximab
B: Palivizumab
Answer: B: Palivizumab 
Explanation: Nomenclature of monoclonal antibodies: * Their name ends with mab. * Before mab the two letters tell the source: - XI means Chimeric - ZU means humanized - U means completely human