Which controlled substance is known to have a high potential for abuse and is classified as Schedule II?

Methylphenidate is classified as a Schedule II controlled substance due to its high potential for abuse. Substances in this category are considered to have a significant risk for addiction and dependence, making their regulation stringent. Methylphenidate is primarily used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy, but its psychoactive properties can lead to misuse, which is why it is tightly controlled under the Controlled Substances Act.

In contrast, the other options provided do not share this high potential for abuse. Prednisone is a corticosteroid used primarily for inflammatory and autoimmune conditions and is not considered to have abuse potential. Levothyroxine is a thyroid hormone replacement therapy, and while it must be used correctly to manage thyroid levels, it does not have addictive properties. Simvastatin is a cholesterol-lowering medication that works to prevent cardiovascular diseases and has no potential for abuse. These factors underscore why methylphenidate stands out as a Schedule II controlled substance.