Which of the following is a characteristic of Schedule I substances?

Schedule I substances are classified as having a high potential for abuse and no accepted medical use in the United States. This classification reflects a consensus in regulatory environments that these substances pose significant risks of addiction or dependence without providing any legitimate therapeutic benefit. Therefore, these substances are considered the most controlled and are illegal to possess, use, or distribute in any context.

In contrast, substances that are categorized in other schedules may have accepted medical uses (as indicated in other options) or are available through prescription or over-the-counter means. Schedule I substances are distinct in that they are viewed as having no safe or effective medical application, leading to their strict prohibition. Understanding this classification is vital for comprehending the legal responsibilities and potential consequences surrounding drug use and distribution.