Which Statement Is False About Complex IV

Which statement is false about complex IV?

A) A binuclear center that contains an iron ion and heme-a₃ is the site of the reduction of molecular oxygen to water.
B) Bacterial and eukaryotic forms of complex IV have very similar structures and number of subunits per functional unit.
C) The core structure of the cytochrome c oxidase in complex IV has three conserved subunits.
D) Copper ions shift from a +2 oxidation state to a +1 oxidation state as electrons are passed through the complex.