Which of the following statements best describes metabolism in human terms?
a: Food is ingested, then digested and broken down into moleucles used in glycolysis and aerobic respiration inside of cells.
b: Food is ingested, then converted into acetaldehyde molecules which some cells use for fuel.
c: Food is ingested, then aggregated to be put into the Kreb's cycle and then finally through glycolysis in order to gain an exponential amout of ATP.
d: Food is ingested, then then fermented by lactobacillus bacteria in our stomach in order to produce B-complex vitamins.