The correct answer is option A (measures 20-300 nanometers), C (infects all forms of living cells), D (does not respond to stimuli) and E (contains DNA or RNA, not both)
The normal size of virus varies from 20 micron to 400 micron. The viruses are the smallest organism that produces infection and thus they not only infect plant, animals , humans but also other microorganism. Viruses do not grow but they have the capability to multiply themselves into large numbers under favorable condition in hosts body. Viruses are unable to respond to stimulus as they do not possess the characteristics of living beings. They at a time can have either DNA or RNA but not both.
