Two People of the Same Gender Consume the Same Amount

Two people of the same gender consume the same amount of alcohol in the same amount of time. Nevertheless, one of them sobers up substantially sooner than the other. MOST likely, this difference is due to differences in:

A) food intake, specifically food eaten immediately after drinking concluded.
B) activity level while drinking; increased activity increases the metabolism rate.
C) liver function; some people's livers metabolize alcohol faster than others' livers.
D) breathing rate; people who breathe more often can exhale the carbon dioxide by-product of alcohol metabolism faster.