Which statement best describes the difference between a virus and bacteria?

The correct statement highlights that a virus is not considered a living organism and cannot be killed with antibiotics, contrasting it with bacteria, which are indeed living single-celled organisms. Viruses lack the cellular structure and metabolic processes that characterize life, meaning they cannot grow or reproduce on their own; they require a host cell to replicate. In contrast, bacteria can be cultured and treated as living entities due to their ability to survive independently, reproduce on their own, and utilize nutrients from their environment.

Additionally, the distinction between treatment methods is important to understand: antibiotics are effective against bacteria but have no effect on viruses. This makes option C the most accurate reflection of the fundamental differences between the two types of pathogens. Understanding these distinctions is crucial for proper diagnosis and treatment in clinical settings, underscoring why this answer is the best choice.