Final answer:
The nurse should first ask about the patient's current medications to manage the hypertensive crisis effectively and understand potential drug interactions with alcohol.
Step-by-step explanation:
The nurse in the emergency department should primarily be concerned with the high blood pressure of 210/105 mm Hg, which is indicative of a hypertensive crisis. Therefore, the first question the nurse should ask is C) "What medications are you currently taking?" This inquiry is crucial because certain medications, including those for depression, can interfere with blood pressure and even lead to a crisis when combined with alcohol. Identifying any antihypertensive medications that the patient may have skipped or other medications that could contribute to these symptoms is of immediate concern to manage the patient's critically high blood pressure and prevent further complications.