<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 24-year-old woman in graduate school comes to the physician for recurrent headaches. The headaches are unilateral, throbbing, and usually preceded by blurring of vision. The symptoms last between 12 and 48 hours and are only relieved by lying down in a dark room. She has approximately two headaches per month and has missed several days of class because of the symptoms. Physical examination is unremarkable. The patient is prescribed an abortive therapy that acts by inducing cerebral vasoconstriction. Which of the following is the most likely mechanism of action of this drug?? A: Inhibition of β1- and β2-adrenergic receptors, B: Activation of 5-HT1 receptors, C: Inhibition of 5-HT and NE reuptake, D: Inhibition of voltage-dependent Na channels, E: Inactivation of GABA degradation,  <response>: This is a clinical vignette describing a patient with symptoms consistent with migraine headaches. The question asks about the most likely mechanism of action of an abortive migraine therapy that induces cerebral vasoconstriction. Based on the description, this is likely referring to a triptan medication used for acute migraine treatment. Triptans are selective 5-HT1B and 5-HT1D receptor agonists that cause vasoconstriction of intracranial extracerebral vessels, thought to be involved in migraine pathogenesis. Choices A and C refer to beta blockers and antidepressants, which are preventive, not abortive migraine therapies. Choice D refers to antiepileptic medications, also used for migraine prevention. Choice E refers to an anticonvulsant mechanism not used for migraine. Only choice B matches the expected mechanism of a triptan abortive migraine medication.B: Activation of 5-HT1 receptors 