Which two entities may apply for re-registration with the DEA 120 days before expiration?

The correct answer pertains to bulk manufacturers and importers of controlled substances classified as Schedule I and II (C1/C2s). In the context of the DEA (Drug Enforcement Administration) regulations, these entities are granted the provision to re-register 120 days before their current registration expires. This applies specifically to entities that deal with the manufacturing and importing of highly controlled substances, as they play a critical role in the supply chain of prescription medications.

Bulk manufacturers are involved in producing larger quantities of controlled substances, while importers bring in these substances from other countries. Given the potential risks associated with C1/C2 substances, the DEA closely monitors these entities and their registrations to ensure compliance with federal regulations aimed at preventing misuse and abuse of controlled substances.

Other options listed involve entities that do not have the same regulatory requirements or do not specifically manage C1/C2 substances as bulk manufacturers and importers do. Understanding the distinction between these types of entities and their roles in the controlled substance supply chain helps clarify why bulk manufacturers and importers are uniquely able to re-register with the DEA well in advance of their registration expiration date.