Which of the following is the best example of a microbiome?

• A. A single Escherichia coli cell in a petri dish
• B. A virus infecting a bacterial cell
• C. The community of microorganisms living in the human gut
• D. A pure culture of Staphylococcus aureus grown in laboratory media

Answer: (C)

Verified step by step guidance

1. Understand the definition of a microbiome: it refers to the entire community of microorganisms (including bacteria, viruses, fungi, and others) living in a specific environment, such as the human gut, soil, or skin.
2. Evaluate each option by considering whether it represents a community of microorganisms or just a single organism or a pure culture.
3. Option 1 describes a single Escherichia coli cell, which is just one microorganism, not a community.
4. Option 2 describes a virus infecting a bacterial cell, which is an interaction between two entities but not a whole community.
5. Option 3 describes the community of microorganisms living in the human gut, which fits the definition of a microbiome as it includes many different microorganisms coexisting in one environment.