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
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 - 
Select and explain. 
A. 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
C: Vaccine prophylaxis of contacts of xavier
Answer: C: Vaccine prophylaxis of contacts of xavier 
Explanation: 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