This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'A woman receives an organ transplant from her sister who is an identical twin. What type of graft is it? \nSelect and explain. \nA. Allograft, B. Autograft, C. Xenograft, D. Isograft', 'role': 'user'}, {'content': 'Answer: D \nExplanation: An Isograft is a graft of tissue between two individuals who are genetically identical (i.e. monozygotic twins). Transplant rejection between two such individuals viually never occurs Ref : Ananthanarayana textbook of Microbiology 9th edition Pgno : 183', 'role': 'assistant'}]