Final answer:
The correct word for putting out a fire by pouring water on it is 'douse'. However, it is important to note that water is not suitable for extinguishing oil fires, as it can cause them to spread.
Step-by-step explanation:
To put out a fire by pouring water on it, the correct word to use is douse. Option 'a' is the appropriate answer to the question. The other options, b) ignite, c) smolder, and d) flare, all relate to the starting or continuing of a fire, not extinguishing it. It is important, however, to recognize that not all fires should be doused with water, as the introductory text's narrative illustrates. For instance, water should never be used on an oil fire, as it can cause the fire to spread.
Combustion is a rapid chemical reaction that combines molecules of oxygen with molecules of fuel, resulting in the release of energy in the form of light and heat. Proper fire extinguishment often involves interrupting this reaction, which can be achieved by dousing, smothering, or chemically interfering with the fire.