Which of the following must be true about a reaction if it is only spontaneous at high temperatures?
A.) It is exothermic, with both negative enthalpy and entropy changes.
B.) It is endothermic, with both positive enthalpy and entropy changes.
C.) It is exothermic, with a negative enthalpy and positive entropy change.
D.) It is endothermic, with a positive enthalpy and negative entropy change.
