This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
[{'content': 'True statement regarding Pneumococcus is \nSelect and explain. \nA. Virulence is due to polysaccharide capsule, B. Capsule is protein in nature, C. Antibodies againts capsule are not protective, D. Resistance to antibiotics has not yet been repoed', 'role': 'user'}, {'content': "Answer: A \nExplanation: The virulence of Streptococcus pneumoniae depends on the capsular polysaccharide. The capsular polysaccharide because of its acidic and hydrophilic propeies, protects the cocci from phagocytosis. Capsulated streptococcus pneumoniae are not phagocytosed efficiently in fluid media or exudates, however, they are susceptible to surface phagocytosis, being engulfed against a firm surface, such as a fibrin clot or epithelium . The enhanced virulence of type 3 Streptococcus pneumoniae is due to the abundance of its capsular material. Non-capsulated strains are avirulent. Antibody to capsular polysaccharide affords protection against infection. Penicillin-resistant strains and strains resistant to erythromycin and tetracycline are found. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 226", 'role': 'assistant'}]