Ans. is 'b' i.e., Poxviruses First see the list of DNA & RNA viruses from above explanation and then read the following impoant facts. . All DNA viruses have double stranded nucleic acid except for Parvovirus, which has single stranded DNA. . All RNA viruses have single stranded nucleic acid except for Reoviridae (Rota virus, Reo virus), which has double stranded RN.4.