Do viruses require living tissue for survival?

Viruses are unique in their biological nature and require a living host to replicate and propagate. Unlike bacteria or other microorganisms that can live independently, viruses lack the cellular machinery necessary for metabolic processes; instead, they depend on the machinery of living cells to reproduce. This dependence on a host organism means that for a virus to survive and multiply, it must invade a living cell, where it can hijack the host's cellular processes.

While it is true that some viruses can remain viable for a limited time outside a host in non-living environments (such as surfaces or airborne droplets), they cannot reproduce or sustain themselves without invading a viable host cell. Thus, the correct answer reflects the essential requirement of living tissue for the reproductive cycle of viruses.