Final answer:
The nurse should clarify the prescription for an MRI of the chest as it is contraindicated for clients with a pacemaker.
Step-by-step explanation:
The nurse should clarify prescription B, which is the request for an MRI of the chest.
Having a pacemaker is a contraindication for an MRI scan because the strong magnetic fields can interfere with the functioning of the pacemaker.
Therefore, the nurse should consult with the healthcare provider and suggest an alternative diagnostic imaging test that does not pose a risk to the pacemaker or the client.