Answer : The correct option is, (b) occur when there is more free energy in the reactants than the products.
Explanation :
Endergonic reactions : It i defined as the reaction in which the energy is absorbed during the reaction.
In endergonic reactions, the Gibbs free energy of product is lower than the reactants. That means, ΔG > 0 and the reaction is non-spontaneous.
Exergonic reactions : It i defined as the reaction in which the energy is released during the reaction.
In exergonic reactions, the Gibbs free energy of product is greater than the reactants. That means, ΔG < 0 and the reaction is spontaneous.
Hence, the endergonic reactions is occur when there is more free energy in the reactants than the products.