What defines possession under 21 USC § 844?

The definition of possession under 21 USC § 844 specifically pertains to the possession of a controlled substance. This statute is part of the Controlled Substances Act, aimed at regulating drugs and other substances that have the potential for abuse and dependency. When looking at the choices, "possession of a controlled substance" is the most aligned with the legal framework established in this section, which addresses illegal possession and outlines penalties for those found in violation of the law regarding controlled substances.

Other options such as possession of synthesis chemicals, legal prescriptions, or personal belongings do not directly pertain to the act of possessing controlled substances as defined by the federal law. For example, possessing a synthesis chemical may relate to drug manufacturing but is not the same as possession under the law in question. Likewise, legal prescriptions are associated with lawful use of medications and are not a concern under this statute unless misused. Personal belongings are outside the purview of controlled substance regulations entirely. Thus, "possession of a controlled substance" accurately encapsulates the legal definition and context of possession as outlined in the law.