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': "A patient (pigeon handler) presents with interstitial pneumonitis accompanied by headache, backache, and a dry, hacking cough. A pale, macular rash is also found on the trunk (Horder's spots). Likely organism is: \nSelect and explain. \nA. Histoplasma, B. Chlamydiae, C. Mycoplasma, D. Aspergillus", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Chlamydiae', 'role': 'assistant'}]