Final answer:
The best example of active listening from the options given is an empathetic response that acknowledges the frustration of waiting and expresses a willingness to act.
Step-by-step explanation:
The response that exemplifies active listening is "I understand. Waiting can be frustrating. Let me see if there's anything I can do to help." Active listening involves acknowledging the other person's feelings and offering assistance. This response shows empathy and conveys a willingness to take action to address the patient's concern. It also reassures the patient that their issue is being taken seriously and that the medical assistant is actively working on a resolution.