I believe the correct answer from the choices listed above the third option. An endothermic reaction is one that uses chemical energy. The term endothermic process describes a process or reaction in which the system absorbs energy from its surroundings; usually, but not always, in the form of heat.
The answer is an chemical energy since the endothermic reaction is any chemical reaction that absorbs heat from its environment. The absorbed energy provides the activation energy for the reaction to occur and results in a net decrease in temperature because absorbed heat from the surroundings is stored in form of the energy in the bonds formed in the reaction.
