The autoclave is a device for heating substances above their boiling point.

• A. The autoclave is a device for heating substances above their boiling point.
• B. It primarily cools materials rapidly.
• C. It measures the pH of solutions.
• D. It incubates samples at low temperatures.

Answer: (A)

Autoclaves sterilize using moist heat under pressure, which allows the temperature to rise above the boiling point of water. By generating steam at high pressure, they typically reach around 121°C at 15 psi, rapidly denaturing proteins and disrupting membranes to kill microorganisms, including spores and viruses. This is why heating substances above their boiling point is exactly what an autoclave does. The other descriptions—cooling materials rapidly, measuring pH, or incubating at low temperatures—describe different equipment or functions and are not what an autoclave is designed for.