Figure 9.3
-What happens at the end of the chain in Figure 9.3?

A) 2 electrons combine with a proton and a molecule of NAD⁺.
B) 2 electrons combine with a molecule of oxygen and two hydrogen atoms.
C) 4 electrons combine with a molecule of oxygen and 4 protons.
D) 4 electrons combine with four hydrogen and two oxygen atoms.
E) 1 electron combines with a molecule of oxygen and a hydrogen atom.