Which of the following statements is true regarding the dea registration number for providers prescribing controlled substances?

a. the dea registration number is necessary for prescribing controlled substances, and it has a three-year validity period before requiring renewal.
b. providers with a dea registration number are authorized to prescribe controlled substances, and the number must be renewed every two years.
c. a dea registration number allows a provider to prescribe controlled substances, but it is valid indefinitely without the need for renewal.
d. the dea registration number is unique to each provider and is valid for five years before renewal is required