Which of the following produces more flame?

Hot air produces more flame compared to boiling water, steam, or sun rays. When air is heated to high temperatures, it expands rapidly, becoming less dense and rising. This convection process is crucial in combustion, as it provides oxygen to support the burning of fuel. When combined with a fuel source, such as a flame or combustible material, the hot air facilitates and sustains combustion, resulting in the production of a visible flame. Boiling water and steam do not inherently produce flames as they are not involved in combustion processes. Sun rays, while capable of igniting certain materials under specific conditions, do not typically produce flames on their own. Therefore, hot air (option [C]) is the most likely to produce a flame when combined with a suitable fuel source.