Which of the Following Statements About the Enthalpy Change of Reaction

Which of the following statements about the enthalpy change of reaction are true? Select all that apply.

A) It has units of J.
B) It is represented by the symbol $\Delta$ G.
C) It measures the exchange of energy with the surroundings during the course of the reaction.
D) It is a measure of the bond-breaking and bond-making which occurs during the course of a reaction.
E) It always has a positive value.