The term 'aerotolerant anaerobe' refers to an organism that:

• A. requires oxygen for growth and cannot survive without it
• B. is killed by the presence of oxygen
• C. uses oxygen for growth but can also grow without it
• D. does not use oxygen for growth but can survive in its presence

Answer: (D)

Verified step by step guidance

1. Understand the definition of different oxygen requirements in microorganisms: obligate aerobes require oxygen to grow, obligate anaerobes are killed by oxygen, facultative anaerobes can grow with or without oxygen and use oxygen when available, and aerotolerant anaerobes do not use oxygen but can tolerate its presence.
2. Focus on the term 'aerotolerant anaerobe' which combines 'anaerobe' (organism that does not require oxygen) and 'aerotolerant' (able to tolerate oxygen).
3. Recognize that aerotolerant anaerobes do not use oxygen for their metabolism, meaning they do not rely on oxygen for growth or energy production.
4. Note that despite not using oxygen, aerotolerant anaerobes can survive and grow in environments where oxygen is present, unlike obligate anaerobes which are harmed by oxygen.
5. Conclude that the correct description of an aerotolerant anaerobe is an organism that does not use oxygen for growth but can survive in its presence.