Which of the following is an example of an incendiary device?

The correct answer, which identifies an incendiary device, is a pressure cooker. This device has the potential to be used deliberately to create an uncontrolled fire or explosion due to the pressure and heat generated during its operation, especially if misused or tampered with.

Candles are commonly associated with fire but are not typically classified as incendiary devices. Their primary purpose is to provide light and heat in a controlled manner. Fire extinguishers are essential tools designed to put out fires, not to initiate them. Similarly, a water hose is a tool used to manage fires by delivering water to extinguish flames, thus making them non-incendiary in nature. Understanding the characteristics that define an incendiary device is crucial in fire investigation, as it helps differentiate between common items and those specifically designed or repurposed to start fires.