During the terminal stages of aerobic respiration, a proton...

During the terminal stages of aerobic respiration, the electron transport chain pumps protons from the mitochondrial matrix into the intermembrane space, creating a proton gradient.

This proton gradient generates a proton motive force. The enzyme complex ATP synthase (Complex V) utilizes this proton gradient to catalyze the synthesis of ATP from ADP and inorganic phosphate ($P_i$) as protons flow back into the matrix through its $F_0$ channel.

Answer: ATP synthase