While on the Phone with a Patient Discussing an Appointment

While on the phone with a patient discussing an appointment, you are interrupted by a second call, which you think might be an important business associate of the physician. How should you handle this situation?

A) Finish your initial conversation with the patient and let the voicemail get the second call. After you hang up with the patient, check the voicemail and return any messages.
B) Excuse yourself to the first caller and answer the second call. Return to the first call as soon as possible, minimizing waiting for all callers.
C) Tell the patient that there is a second call, that it might be an important call you've been expecting, and that you will call back after taking the call.
D) All of these
E) None of these