Which statement below is false?
A. Thermal energy transfers can be tracked as it flows through a system.

B. A constant input of energy, often in the form of heat, is needed to keep an endothermic reaction going.

C. In order to build a chemical bond energy is needed.

D. An exothermic reaction is a chemical reaction in which more energy is needed to break bonds in the reactants than is released when new bonds form in the products.