Why Does the Amount of ATP Produced in Skeletal Muscle

Why does the amount of ATP produced in skeletal muscle differ from the amount produced in other tissues?

A) Skeletal muscle is more efficient than other tissues in the production of ATP.
B) Skeletal muscle transfers electrons via FAD while other tissues use NAD.
C) Skeletal muscle completely oxidizes carbohydrates while other tissues do not.
D) Skeletal muscle has fewer rate-limiting enzymes than do other tissues.