After Administering a Medication to a Client,the Nurse Realizes That

After administering a medication to a client,the nurse realizes that the client was given another client's drug.What must the nurse do next?

A) Administer the original drug,and observe the client frequently for adverse reactions to the first drug.
B) Call the health care provider immediately,and complete an incident report.
C) Check the client's MAR for drug allergies,and if there is no indicated allergy to the drug administered in error,no further action is necessary.
D) Document the error on the client's medical record,and notify the supervisor.