What is a characteristic of viruses?

A characteristic of viruses is that they must live on a host cell to reproduce. Unlike bacteria, which can grow and multiply independently, viruses lack the cellular machinery necessary for metabolism and reproduction. They are essentially packages of genetic material (DNA or RNA) encased in a protein coat and cannot carry out life processes on their own. Instead, they invade a host cell, hijacking the cell’s machinery to replicate themselves. This dependence on a host cell for reproduction distinguishes viruses from other microorganisms, such as bacteria and fungi, that can exist and reproduce independently in various environments.

The other options do not accurately describe characteristics of viruses. For example, viruses are generally much smaller than bacteria, contradicting the assertion that they are larger. Additionally, while some viruses infect plants, many are known to infect animals and humans as well, making the statement that they only infect plants inaccurate.