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
Virulence factors for meningococci 
Select and explain. 
A. Capsule, B. Pili, C. Endotoxin, D. Coagulase
A: Capsule
Answer: A: Capsule 
Explanation: Meningococci are capsulated, unlike Neisseria. Based on their capsular polysaccharide antigens, they are classified into 13 subgroups, of which groups A, B, C, X, Y and W-135 are the most impoant Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 231