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': 'All of the following are true regarding diphtheria except- \nSelect and explain. \nA. Tonsillar membrane cab be easily wiped off, B. There may be swelling of neck causing bull neck appearance, C. With high degree of immunity a membrane may never appear, D. In laryngeal diphtheria, tracheostomy may be needed to relieve respiratory obstruction', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]