The complete reactions of cellular respiration in the presence of oxygen ($C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + energy$) result in which of the following?
A) oxidation of $O_2$ and reduction of $H_2O$
B) oxidation of $C_6H_{12}O_6$ and reduction of $O_2$
C) reduction of $CO_2$ and oxidation of $O_2$
D) reduction of $C_6H_{12}O_6$ and oxidation of $O_2$