Which of the Following is a Well Known,well Established Viral

Question

Which of the following is a well known,well established viral disease,rather than an emergent one?
A)SARS
B)Avian influenza
C)Ebola
D)Smallpox
E)West Nile encephalitis

Accepted Answer

Emergent diseases are ones that we newly recognize as causing infections in people.Smallpox has been recently eradicated,but caused disease in humans for thousands of years.