What is one similarity between viruses and viroids? A. both may be comprised of small RNA molecules B. both have genomes that code for a few enzymes C. both have their genomes enclosed by a protein covering D. both can infect animal, plant and bacterial cells A. both may be comprised of small RNA molecules B. both have genomes that code for a few enzymes C. both have their genomes enclosed by a protein covering D. both can infect animal, plant and bacterial cells .