Viruses cannot multiply on their own because they:

Explanation

Viruses cannot multiply on their own because they lack the cellular machinery required for independent life processes. Unlike living cells, viruses do not have ribosomes, enzymes for energy production, or the ability to synthesize proteins. Their genetic material, whether DNA or RNA, cannot be expressed or replicated without the help of a host cell. Therefore, viruses must infect living cells and hijack the host's transcription and translation machinery to produce viral proteins and replicate their genome. This absolute dependence on a host cell for reproduction is why viruses are considered obligate intracellular parasites.