Who Among the Following Is Most Likely to Have the Lowest

Who among the following is most likely to have the lowest rate of drug metabolism?

A) 62-year-old Edward, whose liver is showing symptoms of poor blood circulation
B) 30-year-old Estella, who is following a protein-rich diet
C) 21-year-old Fabiola, who often consumes alcohol when she goes out
D) 60-year-old John, who smokes occasionally