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: Microbiology
[{'content': 'One of the following about corynebacterium diphtheriae is wrong - \nSelect and explain. \nA. Gram negative, B. Ernest babes granules seen, C. Chinese letter pattern, D. Prevented by immunisation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]