During Periods of Fasting, Fat Is Said to Have a Protein-Sparing

During periods of fasting, fat is said to have a protein-sparing effect because the body

A) oxidizes its spare protein before it depletes its fat reserves.
B) metabolizes fats and proteins through the same metabolic pathways.
C) must have an adequate fat intake in order to absorb and metabolize proteins.
D) must have an adequate protein intake in order to absorb and metabolize fats.
E) does not oxidize its proteins unless it has consumed its fat reserves first.