This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'Xavier and yogender stay in the same hostel of same university. Xavier develops infection due to group B meningococcus. After few days yogender develops infection due to Group C meningococcus. All of the following are true statements except - \nSelect and explain. \nA. Educate students about meningococcal transmission and take preventive measures, B. Chemoprophylaxis to all against both group B and group C, C. Vaccine prophylaxis of contacts of xavier, D. Vaccine prophylaxis of contacts of yogender', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Park&;s texbook of Preventive and Social Medicine 23rd edition Page no: 166 Currently available meningococcal vaccines include polysaccharide vaccines and polysaccharide-protein conjugate vaccines. Both vaccines are available against meaningococci of serogroup A, C, W135 and Y', 'role': 'assistant'}]