This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hepatitis, Subject name: Medicine
[{'content': 'Which of the following hepatitis has worst prognosis? \nSelect and explain. \nA. HBV HDV co-infection, B. HDV super infection on HBV, C. HBV alone, D. HDV alone', 'role': 'user'}, {'content': "Answer: B \nExplanation: ANSWER: (B) HDV super infection on HBVREF: Harrison's 17th ed chapter 300Though prognosis of HDV with HBV is a bad prognosis, however prognosis of super infection is worse than coinfection.", 'role': 'assistant'}]