Answer:
(A) proceeding without external influence once it has begun.
Step-by-step explanation:
A reaction that is spontaneous can be described as
(A) proceeding without external influence once it has begun. TRUE. A spontaneous reaction has a tendency to proceed in the way it has begun. It is spontaneous when Gibbs free energy is negative.
(B) releasing heat to the surroundings. FALSE. If the reaction is exothermic (enthalpy negative), one still has to take into account the effect of the entropy on Gibbs free energy.
(C) proceeding in both the forward and reverse directions. FALSE. This just means that the reaction is reversible.
(D) increasing in disorder. FALSE. This means that entropy increases but it is still necessary to take into account the effect of enthalpy on Gibbs free energy.
(E) having the same rate in both the forward and reverse directions. FALSE. This is related to the kinetics but not the spontaneity.