1. The problem asks why fire is hot and bright during burning. 2. Burning is a chemical reaction called combustion where reactants (like fuel and oxygen) react to form products. 3. During combustion, stored chemical energy in the fuel is released as heat and light. 4. This release of energy makes the fire hot and bright. 5. The correct explanation is: Stored energy is released. 6. Other options like oxygen creating light or energy absorption from surroundings are incorrect because oxygen supports combustion but does not create light itself, and energy is released, not absorbed. 7. Reactants do not cool down; they transform and release energy. Final answer: Stored energy is released.