Some friends are trying to make wine in their basement. They've added yeast to a
sweet grape juice mixture and have allowed the yeast to grow. After several days
they find that sugar levels in the grape juice have dropped, but there's no alcohol in
the mixture. The most likely explanation is that
A) the yeast used the alcohol as a carbon source.
B) the mixture needs less oxygen, because yeast only produce alcohol in the
absence of oxygen.
C) the mixture needs more sugar, because yeast need a lot of energy.
D) the mixture needs less sugar, because high sugar concentrations stimulate
cellular respiration, and alcohol is not a by-product of cellular respiration.
E) the mixture needs more oxygen, because yeast need