Which statement does NOT describe one of the differences between the inner and outer mitochondrial membranes?

a. The outer mitochondrial membrane contains porins, whereas the inner mitochondrial membrane does not.
b. There is a larger pH gradient across the inner mitochondrial membrane than the outer mitochondrial membrane.
c. The outer mitochondrial membrane is permeable to large proteins (MW > 10,000 Daltons), whereas the inner mitochondrial membrane is not.
d. The inner mitochondrial membrane contains a smaller percentage of lipid relative to protein when compared with the outer mitochondrial membrane.
e. The outer mitochondrial membrane has a smaller surface area than the inner mitochondrial membrane.