Final answer:
The hypothesis proposed by Peter Mitchell that describes the coupling of chemiosmotic mechanisms and electron transport is concerned with how a proton gradient is utilized to synthesize ATP, known as ATP synthesis.
Step-by-step explanation:
Peter Mitchell proposed the hypothesis that describes how chemiosmotic mechanisms and electron transport are coupled. The correct answer to the question is d) Chemiosmotic; electron transport; ATP synthesis.
The chemiosmotic mechanism explained how the creation of an electrochemical gradient and how gradient free energy ends up in ATP. This process occurs in the mitochondria, where the end products of electron transport are NAD+, FAD, water, and protons. The protons are pumped across the cristae membrane, utilizing the energy from electron transport, consequently forming a proton gradient that stores free energy. This proton-motive force then drives the production of ATP as protons flow back into the mitochondrial matrix through ATP synthase.