**Core Concept**
Prazosin is an alpha-1 adrenergic receptor antagonist used to manage hypertension and symptomatic treatment of benign prostatic hyperplasia. However, its application in treating scorpion sting-induced pulmonary edema is a specific clinical scenario.

**Why the Correct Answer is Right**
Scorpion stings can cause an intense release of catecholamines, leading to severe hypertension and subsequent pulmonary edema. Prazosin's alpha-1 adrenergic receptor antagonism helps alleviate this sympathetic storm by blocking the vasoconstrictive effects of catecholamines on blood vessels. This mechanism reduces peripheral resistance, thereby lowering blood pressure and alleviating pulmonary congestion. Prazosin's rapid onset of action makes it an effective choice in this emergency scenario.

**Why Each Wrong Option is Incorrect**
**Option B:** Clonidine is an alpha-2 adrenergic receptor agonist that can reduce sympathetic outflow but is not the primary choice for acute management of scorpion sting-induced pulmonary edema.
**Option C:** Furosemide is a loop diuretic used to treat fluid overload but does not address the underlying pathophysiology of scorpion sting-induced pulmonary edema.
**Option D:** Mannitol is an osmotic diuretic used to reduce intracranial pressure and manage cerebral edema but is not indicated for pulmonary edema due to scorpion stings.

**Clinical Pearl / High-Yield Fact**
Recall that scorpion stings can cause a catecholamine surge, leading to hypertension and pulmonary edema. Prazosin's alpha-1 adrenergic receptor antagonism can rapidly alleviate this condition, making it a crucial medication to know in emergency medicine.

✓ Correct Answer: A. Prazosin.