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': 'All of the following are true about Chlamydia except- \nSelect and explain. \nA. Gram positive, B. Causes trachoma, C. Causative organism of psittacosis, D. Are also called basophilic viruses', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]