During ATP Synthesis by Oxidative Phosphorylation

During ATP synthesis by oxidative phosphorylation,

A) hydrogen ions pass from the mitochondrial matrix to the intermembrane space, activating ATP synthase.
B) hydrogen ions pass from the intermembrane space to the mitochondrial matrix, activating ATP synthase.
C) water passes from the mitochondrial matrix to the intermembrane space, activating ATP synthase.
D) water passes from the intermembrane space to the mitochondrial matrix, activating ATP synthase.