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: Pharmacology
Which of the following is used as prophylaxis for meningococcal meningitis ? 
Select and explain. 
A. Gentamicin, B. Erythromycin, C. Rifampicin, D. Chloramphenicol
C: Rifampicin
Answer: C: Rifampicin 
Explanation: None