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: Medicine
[{'content': 'The most common cause of Kaposi sarcoma? \nSelect and explain. \nA. HHV7, B. HHV8, C. HHV9, D. HHV6', 'role': 'user'}, {'content': "Answer: B \nExplanation: Human herpesvirus type 8 is believed to be the cause of most cases of Kaposi's sarcoma. Roseola Infantum (Exanthem Subitum)has more than one cause: the most common is human herpesvirus type 6 and, less frequently, human herpesvirus type 7. Ref:Harrison's Principles of Internal Medicine, 18e, Chapter 119.Introduction to Infectious Diseases.", 'role': 'assistant'}]