This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Pathology
Post transplant lymphoma occurs due to proliferation of which of the following cells - 
Select and explain. 
A. T cell, B. B cell, C. NK cell, D. Monocyte
B: B cell
Answer: B: B cell 
Explanation: Diffuse large B cell lymphoma (DLBCL) is the diffuse counterpa of follicular large cleaved cell lymphoma. Epstein Barr virus infectin has been etiologically implicated in DLBCL in immunosuppresed patients of AIDS and organ transplant cases Reference : Harsh Mohan textbook of pathology, 7th edition.Pg no.357