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
In an outbreak of cholera in a village of 2000 population 20 cases have occurred and 5 have died. Case fatality rate is ? 
Select and explain. 
A. 1%, B. 0.25%, C. 5%, D. 25%
D: 25%
Answer: D: 25% 
Explanation: Ans. is `d' i.e., 25%