Since It Is a Virus Which Cooperatively Helps Grass to Grow

Since it is a virus which cooperatively helps grass to grow at 65 ^$\circ$ C,based on what could the virus be detected?

A) by the presence of antibodies to the virus
B) by the presence of double-stranded RNA
C) by signs of infection
D) by the ability to grow at 65 ^$\circ$ C
E) by the presence of viral proteins