When Does an Endothermic Reaction Occur

When does an endothermic reaction occur?

A) when the enthalpy of the reactants is greater than the enthalpy of the products
B) when bonds are formed
C) when the energy of bonds breaking is greater than the energy of bonds formed
D) when the energy of bonds breaking is less than the energy of bonds formed
E) when stronger bonds are formed and weaker bonds are broken