A nurse is reviewing a client's prescription for haloperidol 2 mg every 4 hr PRN agitation. Before administering this medication, the nurse should ask the provider to add which of the following components of a medication prescription?

A. Dose: The dose of 2 mg is clearly specified in the prescription and does not need further clarification. It is the correct amount to administer based on the provided information. B. Route: The route of administration for haloperidol should be specified if it is not included in the prescription. Haloperidol can be administered orally, intramuscularly, or intravenously, and knowing the correct route is crucial to ensure proper and effective administration of the medication. C. Frequency: The frequency is indicated as "every 4 hr PRN" (as needed), which specifies how often the medication can be given. There is no need for further clarification regarding the frequency. D. Medication: The medication, haloperidol, is already identified in the prescription. There is no need to ask for clarification regarding the medication itself, as it is clearly stated.