What is required for a Schedule III controlled substance to be exempt from controlled substances law?

A Schedule III controlled substance can be exempt from controlled substances law when it is combined with specific ingredients, such as a barbiturate or benzodiazepine. This is because certain combinations in specified formulations may lead to a product that is deemed to have lower potential for abuse or dependency. The law recognizes that when these controlled substances are mixed with other specific substances, they may meet criteria for exemption, allowing for broader use under regulated conditions.

The other options do not align with how substances are classified under controlled substances law. Simply being packaged in small quantities does not affect a substance's controlled status. Labeling a product as non-controlled would have no legal impact unless it meets set criteria outlined by the law. Additionally, being registered under state law pertains to legal compliance and not necessarily to the classification or exemption of a substance. These factors distinguish the correct choice by highlighting how specific formulations can alter the controlled status of a substance.