An Illness Outbreak Occurs in New York City Birds in the Late

An illness outbreak occurs in New York City birds in the late 1990s. After a lengthy scientific investigation, the Centers for Disease Control (CDC) determine that the agent causing the birds to die is the West Nile virus. Outbreaks of this illness have been observed in several other countries in Asia and the Middle East across the last 50 years, but not in the United States. With this information, what would be the best categorization of this infectious agent/disease?

A) This is a reemerging infection. It is been around for a long time, and it is reappearing in a susceptible population again.
B) This is a nosocomial (hospital-acquired)  infection. It is transmitted from animals to human beings in urban environments.
C) This is an emerging infection. It hasn't been around that long, and it has made a jump across continents into a new susceptible population.
D) This is an unimportant infection that not a concern to human beings because it occurs in birds, so there is no need to classify it.
E) This is a chronic infection. It has been around for many years, and it has made a jump across continents into a new susceptible population.