Final answer:
Viruses are nonliving entities as they do not possess most of the defining traits of living organisms. Viruses rely on host cell machinery for replication, thus separating them from living organisms. They infect host cells and use their machinery to reproduce.
Step-by-step explanation:
A virus is a nonliving entity because it does not possess most of the defining traits of living organisms. Viruses rely on host cell machinery for replication, which is a characteristic that separates them from living organisms. They lack a cellular structure and organelles and cannot carry out life processes such as metabolism or growth. Instead, viruses infect host cells and use their machinery to reproduce and make copies of themselves.