Although in higher animals fats are the most efficient storage form of "free-energy," not all ingested carbohydrate is converted to fat. Some is stored in the form of glycogen. Which statement does NOT apply to the metabolic benefits of storing "free-energy" in the form of glycogen?

a. Glycogen can be rapidly catabolized because its structure allows for several catabolic enzymes to work in parallel.
b. Glycogen in skeletal muscle can be mobilized under anaerobic conditions, whereas products of fatty acid catabolism cannot.
c. In contrast to glycogen, the products of fatty acid catabolism are not gluconeogenic.
d. Erythrocytes have an absolute requirement for glucose and cannot use any product of fat metabolism for their energy needs.
e. Glycogen molecules are highly hydrated.