Which individual must register with the DEA for controlled substance activities?

In the context of the question regarding who must register with the DEA for controlled substance activities, the correct choice is the dentist who writes prescriptions after a dental procedure. Individuals who prescribe controlled substances, including dentists, must be registered with the DEA. This regulation ensures that those who have the authority to prescribe medications have undergone the necessary training and are subject to oversight.

Prescribing controlled substances is a significant responsibility, and registration ensures that practitioners comply with federal laws governing such medications. By registering with the DEA, the dentist is allowed to maintain a controlled substance registration and can legally prescribe medications, thus ensuring the protection of public health and safety.

In contrast, pharmacy technicians and pharmacists in their roles of counting tablets and verifying orders typically do not need their own DEA registration, as they are acting under the authority of the pharmacy's registration. Their activities are typically considered part of the operations of the pharmacy rather than controlled substance prescribing. The resident physician in this scenario may not need to register with the DEA if they are working under a supervising physician's DEA number while writing prescriptions.