In comparing the demand for insulin with the demand for vitamins over the next decade, which of the following statements is TRUE?

a. The demand for insulin is more elastic than the demand for vitamins over the next decade because consumers are more reactive to changes in the price of vitamins.
b. The demand for insulin is less elastic than the demand for vitamins over the next decade because consumers are more reactive to changes in the price of insulin.
c. The demand for insulin is less elastic than the demand for vitamins over the next decade because consumers are more reactive to changes in the price of vitamins.
d. The demand for insulin is more elastic than the demand for vitamins over the next decade because consumers are more reactive to changes in the price of insulin.