Entities exhibiting properties of both non-living and living are:

The correct option is viruses.

Viruses are unique biological entities that exist on the borderline between living and non-living things. They demonstrate characteristics of both categories depending on whether they are inside or outside a host organism.

Here is a step-by-step breakdown of why viruses exhibit properties of both non-living and living systems:

1. Non-Living Properties of Viruses:
Outside of a living host cell, viruses behave like inert chemicals. Their non-living characteristics include:
• Acellular Structure: Unlike all living organisms, viruses do not have a cellular structure. They lack cytoplasm, cell membranes, and cell organelles.
• Lack of Metabolism: They do not perform metabolic activities such as respiration, digestion, or protein synthesis on their own.
• Crystallizability: Viruses can be crystallized and stored in a bottle for years, much like non-living chemical compounds.

2. Living Properties of Viruses:
Once they infect a host cell, they utilize the host's cellular machinery to exhibit living characteristics, including:
• Genetic Material: They possess genetic material, either DNA or RNA, which carries genetic information.
• Reproduction and Replication: Inside a host, they replicate rapidly to produce offspring (new viral particles).
• Mutation and Evolution: Viruses can mutate and evolve over time, which is a key characteristic of living systems.

Therefore, because they display cellular inertia outside a host but replicate and evolve inside a host, viruses are considered a bridge between the living and non-living worlds.