Viral Classification Has Changed Over the Years and While They

Viral classification has changed over the years and while they are given genus names, the use of species names has not been widely accepted.This is because

A) viruses are not organisms.
B) viruses change over time making species characteristics difficult to stabilize.
C) viruses that could be classified into a single species may have many, but not all, properties in common.
D) All of the above are arguments against using species designations for viruses.