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: Social & Preventive Medicine
Case fatality rate is a method of measuring ? 
Select and explain. 
A. Infectivity, B. Pathogenecity, C. Virulence, D. Average duration of disease
C: Virulence
Answer: C: Virulence 
Explanation: Ans. is 'c' i.e., Virulence CFR is closely related to virulence of agent.