Which statement about Clostridium tetani environmental preference is accurate?

• A. It thrives only in warm environments
• B. It thrives in either cold or warm environments
• C. It thrives only in cold environments
• D. It cannot survive in moist environments

Answer: (B)

Clostridium tetani is an obligate anaerobe, so it grows best where oxygen is scarce and forms hardy spores that can persist in soil and organic matter through varying conditions. Those spores are very resilient, capable of surviving through different temperatures and seasons, even when the environment itself isn’t consistently warm. When an anaerobic niche appears—such as in a deep, closed wound or in moist, muddy soil—these spores can germinate and the bacteria can grow at body temperature to produce toxin. Because of this spore resilience, the organism can be found in both cooler and warmer environments, making the statement that it thrives in either cold or warm environments the most accurate among the options. It doesn’t rely on moisture-free conditions alone, and moisture can support the environments where germination and growth occur.