This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology Pa 1 (Immune Response, Antigen-Antibody Reactions, Hypersensitivity, Structure of Immune System, Immunodeficiency Disorders), Subject name: Microbiology
[{'content': 'Common between B and T cells - (PGI Nov 14) \nSelect and explain. \nA. Origin from same cell lineage, B. Site differentiation, C. Antigenic mark, D. Both humoral and cellular immunity', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 1. Both T and B cells originate from same cell lineage - Lymphoid lineage 2. But, differentiation occurs at different sites-T-cell in Thymus & B-cell in Bone marrow.', 'role': 'assistant'}]