A 25-Year-Old Man Is Found in a Semicomatose State and Is

A 25-year-old man is found in a semicomatose state and is taken to the emergency room by friends, who say that the man has not eaten for the past 5 days.Which of the following substances is this patient's primary source of glucose?

A) Amino acids from liver proteins.
B) Amino acids from muscle proteins.
C) Liver glycogen.
D) Muscle glycogen.
E) Fatty acids from adipose tissue.