In mitochondria, exergonic redox reactions
a. are the source of energy driving prokaryotic atp synthesis.
b. provide the energy that establishes the proton gradient.
c. reduce carbon atoms to carbon dioxide.
d. are coupled via phosphorylated intermediates to endergonic processes.

The correct answer is option b.

Explanation:

Exergonic reactions refer to the reactions that cause loss of energy in the form of heat. They are not the mediating force for the synthesis of ATP in prokaryotes. The procedure of ATP synthesis is distinct in prokaryotes and eukaryotes in various aspects.  

In mitochondria, the exergonic reactions provide energy, which assists in establishing a proton gradient. This proton gradient plays an essential part in the generation of ATP by ATP synthase via oxidative phosphorylation.