**Core Concept**
Sumatriptan is a selective serotonin receptor agonist, specifically targeting the 5-HT1B and 5-HT1D receptors, which play a crucial role in the pathophysiology of migraine headaches.

**Why the Correct Answer is Right**
Sumatriptan acts on these receptors by inducing vasoconstriction of the intracranial blood vessels, which helps to alleviate the throbbing pain associated with migraines. The agonistic effect on 5-HT1B and 5-HT1D receptors also inhibits the release of pro-inflammatory neuropeptides and neurotransmitters, further contributing to the analgesic effect. This selective action on these receptors minimizes the risk of adverse effects, making sumatriptan a well-tolerated treatment option for migraines.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as sumatriptan does not act on alpha-2 adrenergic receptors, which are involved in the regulation of blood pressure and sympathetic nervous system activity.
* **Option B:** This option is incorrect as sumatriptan does not act on dopamine receptors, which are primarily involved in motor control, reward, and motivation.
* **Option C:** This option is incorrect as sumatriptan does not act on muscarinic receptors, which are involved in the parasympathetic nervous system and regulate various bodily functions such as heart rate and digestion.

**Clinical Pearl / High-Yield Fact**
Sumatriptan is a first-line treatment for acute migraines due to its rapid onset of action and high efficacy in relieving pain. However, it is essential to note that sumatriptan is contraindicated in patients with coronary artery disease or other cardiovascular conditions, as it can cause vasoconstriction and potentially exacerbate these conditions.

**Correct Answer:** C. 5-HT1B and 5-HT1D receptors.