Microbes that live stably in and on the human body are called the:

• A. pathogens
• B. opportunistic organisms
• C. normal microbiota
• D. extremophiles

Answer: (C)

Verified step by step guidance

1. Understand the definition of each term: 'pathogens' are microbes that cause disease; 'opportunistic organisms' cause disease only when the host's defenses are compromised; 'extremophiles' are organisms that thrive in extreme environments.
2. Recognize that microbes living stably in and on the human body without causing harm are part of the body's natural microbial community.
3. Recall that the term for these stable, non-harmful microbes is 'normal microbiota' or 'normal flora'.
4. Identify that 'normal microbiota' play important roles such as protecting against pathogens and aiding in digestion.
5. Conclude that the correct term for microbes living stably in and on the human body is 'normal microbiota'.