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': 'Which one of the following statement regarding Chlamydia pneumoniae is TRUE? \nSelect and explain. \nA. Fifteen serovars have been identified as human pathogens, B. It is transmitted through the inhalation of bird excreta, C. The cytoplasmic inclusions present in the sputum specimen are rich in glycogen, D. The group specific antigen is responsible for the production of complement fixing antibodies', 'role': 'user'}, {'content': "Answer: D \nExplanation: Chlamydiae possess group specific antigens. These are heat-stable lipopolysaccharides with 2-keto-3-deoxyoctanoic acid as an immunodominant component. Antibody to these genus-specific antigens are detected by complement fixation (CF) and immunofluorescence. Ref: Harrisons Internal Medicine, 18th Edition, Chapter 176; Jawetz, Melnick and Adelberg's Medical Microbiology, 25th Edition, Chapter 27", 'role': 'assistant'}]