This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Virology, Subject name: Microbiology
[{'content': 'Hepatitis A virus is best diagnosed by - \nSelect and explain. \nA. IgM antibodies in serum, B. Isolation from stool, C. Culture from blood, D. Isolation from bile', 'role': 'user'}, {'content': 'Answer: A \nExplanation: HAV best diagnosed by demonstration of IgM antibody in serum REF:<\\p> ANATHANARAYANAN MICROBIOLOGY NINTH EDITION PAGE.542', 'role': 'assistant'}]