The correct answer is a synthesis reaction.
A synthesis reaction is a kind of reaction in which various reactants merge to produce a single product. Synthesis reactions discharge energy in the form of light and heat, so they are exothermic. An illustration of a synthesis reaction is the production of water from hydrogen and oxygen.
In the process of forming water, that is, two molecules of water, one molecule of diatomic oxygen must be combined with the two molecules of water, in the process energy will be released.
