The difference between an exergonic reaction and an endergonic reaction is that an exergonic reaction involves release of energy, while an endergonic reaction involves absorption of energy.
In an exergonic reaction, energy is released to the surroundings. The bonds being formed are stronger than the bonds being broken. In an endergonic reaction, energy is absorbed from the surroundings.
The correct answer between all the choices given is the third choice or letter C. I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.