Boiling is not reliable for sterilization because:

• A. boiling destroys all forms of microbial life instantly
• B. some bacterial endospores can survive boiling temperatures
• C. boiling is only effective against viruses, not bacteria
• D. boiling increases the growth rate of most bacteria

Answer: (B)

Verified step by step guidance

1. Understand the concept of sterilization: Sterilization is the process of killing or removing all forms of microbial life, including bacteria, viruses, fungi, and spores.
2. Recognize that boiling involves heating water to 100°C, which is effective at killing many vegetative (actively growing) bacterial cells and viruses.
3. Recall that bacterial endospores are a dormant, highly resistant form of bacteria that can survive extreme conditions, including boiling temperatures for a limited time.
4. Analyze why boiling is not reliable for sterilization: since some bacterial endospores can survive boiling, boiling does not guarantee complete sterilization.
5. Conclude that more rigorous methods, such as autoclaving (using pressurized steam at higher temperatures), are required to reliably sterilize materials by killing endospores.