Which of the following is an example of an exothermic reaction?

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An example of an exothermic reaction is the combustion of fuels. In an exothermic reaction, energy is released into the surroundings, typically in the form of heat. During combustion, organic materials like hydrocarbons react with oxygen to produce carbon dioxide, water, and energy. This release of energy is what makes combustion exothermic; it leads to an increase in temperature in the surroundings, such as in a fire or when burning fossil fuels.

In contrast, photosynthesis is an endothermic process where plants absorb sunlight to convert carbon dioxide and water into glucose and oxygen. The melting of ice is also an endothermic reaction, as ice absorbs heat to change its state to water without raising its temperature. Similarly, the electrolysis of water involves breaking down water into hydrogen and oxygen gas using electrical energy, which is another endothermic process. Thus, the combustion of fuels is distinct as it is a clear example of an exothermic reaction.