This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Transplantation, Subject name: Surgery
[{'content': 'Xeno transplantation of heart in human being, which of the animal heart has been used? \nSelect and explain. \nA. Pig, B. Horse, C. Dog, D. Rabbit', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) PigRef: Internet Source* Xeno transplant of Piglet heart is tried and has shown successful survival in humans for 200 days.* Pigs were chosen because their anatomy is more or less same like human anatomy.', 'role': 'assistant'}]