Which statement is most accurate concerning how photosystem II (PS II) compares to the electron transport chain (ETC) of mitochondria? A) In both systems, ATP is produced by chemiosmosis. B) In both systems, high-energy electrons come from NADH. C) The ETC associated with PS II shares no similar components with the ETC of mitochondria. D) PS II produces ATP by chemiosmosis; the ETC of mitochondria produces ATP by substrate-level phosphorylation.