What does 21 USC 844 specifically prohibit?

The prohibition outlined in 21 USC 844 addresses the possession of controlled substances. Specifically, it prohibits individuals from knowingly or intentionally possessing a controlled substance. In the context of the choices presented, the correct answer is focused on the possession of these substances aboard vessels within 3 nautical miles (NM) from the shore, which is a jurisdictional limit for U.S. law enforcement in maritime contexts.

This regulation is crucial because it empowers law enforcement to address drug-related offenses in close proximity to U.S. waters, supporting public safety and legal norms regarding the control of substances recognized as illegal or regulated. Thus, option B accurately reflects the legal framework established under this section of the U.S. Code by emphasizing the specific maritime jurisdiction where possession of controlled substances is prohibited.

In contrast, while the other options pertain to related topics of controlled substances, they do not capture the specific focus of 21 USC 844 concerning possession within the defined maritime boundaries.