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
[{'content': 'Pembrolizumab is \nSelect and explain. \nA. CTLA4 inhibitor, B. Monoclonal antibody against PDL1 receptor, C. Monoclonal antibody against PD1 ligand, D. Monochonal antibody against CDK416', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Pembrolizumab and Nevolumab are monoclonal antibodies against PDL1 receptor used in BRAF -ve malignant melanoma.', 'role': 'assistant'}]