Which of the following is identified as Schedule II?

Schedule II substances are classified by their high potential for abuse, leading to severe psychological or physical dependence, but they also have accepted medical uses in the United States. MS Contin, which is an extended-release formulation of morphine, falls into this category because it is a powerful opioid used for managing severe pain. Due to its potential for addiction and misuse, it is strictly regulated under the Controlled Substances Act.

In contrast, LSD, Peyote, and Marijuana are classified under different schedules. LSD is a Schedule I substance, indicating it has no accepted medical use and a high potential for abuse. Peyote is similarly classified as Schedule I, as it is a hallucinogenic drug. Marijuana remains a complex case, as while it is classified as Schedule I at the federal level, some states have legalized its use for medical or recreational purposes. However, none of these alternatives possess the characteristics of a Schedule II substance as effectively as MS Contin does, making it the clear choice in this case.