The Reaction, , Where En Represents Ethylenediamine, Has a Small $\Delta$

The reaction, , where en represents ethylenediamine, has a small value for the enthalpy change, $\Delta$ H_rxn, yet the free-energy change is large because

A) the reaction rate is fast.
B) the entropy change is large and positive.
C) the enthalpy change is large enough to matter.
D) the entropy change is large and negative.
E) ethylenediamine has amino groups that are stronger bases than ammonia.