In Eukaryotes, the Proton-Motive Force Allows Protons to Move Passively

In eukaryotes, the proton-motive force allows protons to move passively through ATP synthase in which direction?

A) From the outside of the cell to the cytosol
B) From the mitochondrial matrix to the inner mitochondrial membrane space
C) From the cytoplasm to the mitochondrial matrix
D) From the cytoplasm to the mitochondrial inner membrane space
E) From the mitochondrial inner membrane space to the mitochondrial matrix