81. β-oxidation of fatty acids, which one of the following reactions is correct?
(A) Two NADH are produced for each acetyl-CoA.
(B) Oxidation of an 18-carbon fatty acid produces six molecules of propionyl-CoA.
(C) Uses only even–chain, saturated fatty acids as substrates.
(D) Uses NADP+.
(E) Occurs by a repeated sequence of four reactions.