Influenza strains that sweep around the world often carry names such as H5N1 or H2N2.If they are both flu viruses,why do they differ in their H and N numbers?
A)The H and N numbers indicate the geographical region in which the virus was discovered. B)The H and N numbers indicate the order in which the virus was discovered. C)The H and N numbers indicate the toxicity of the virus to humans and nonhumans. D)The H and N numbers indicate the type of glycoprotein spikes found in the viral envelope.