Sort the following molecules to reflect the order in which they carry electrons in the respiratory chain. Your answer would be a seven-letter string composed of letters A to G only, e.g. GFADCBE.
(A) NADH dehydrogenase complex
(B) Cytochrome c oxidase complex
(C) Cytochrome c reductase complex
(D) Cytochrome c
(E) Ubiquinone
(F) NADH
(G) H?O