Answer: they cannot reproduce on their own.
Explanation:
Viruses are infectious ultramicroscopic particles formed by nucleic acid (s), DNA and/or RNA, surrounded by a protein envelope, which is sometimes coated with a lipid membrane called capsid. Prokaryotic and eukaryotic cells have both types of nucleic acids to metabolize and reproduce.
Viruses do not replicate independently of cells, and in the extracellular environment, they are characterized by a mature infectious form, the virion, a complete, fully developed viral particle. The human being lives with the viruses since birth, but some situations, professions, social circumstances and certain Personal habits increase the likelihood of the individual contact certain types of viruses. Poor hygiene and coexistence in crowded places can be a constant source of viral infections, especially due to organisms disseminated through the respiratory and fecal-oral routes.