Which of the following medications is commonly used to treat hypertension by relaxing blood vessels?

Correct Answer: A

Rationale: The correct answer is Amlodipine (A) because it is a calcium channel blocker that works by relaxing blood vessels, leading to lower blood pressure. Amlodipine specifically targets smooth muscle cells in blood vessels, causing vasodilation and reducing the workload on the heart. Hydrochlorothiazide (B) is a diuretic that works by increasing urine output but does not directly relax blood vessels. Losartan (C) is an angiotensin II receptor blocker that blocks the vasoconstrictor effects of angiotensin II but does not directly relax blood vessels. Enalapril (D) is an ACE inhibitor that also blocks vasoconstriction effects but does not directly relax blood vessels.

Correct Answer: A

Rationale: Rationale: Clarithromycin is the correct choice because it is commonly used in combination therapy to treat Helicobacter pylori infections. It is often prescribed along with other antibiotics like amoxicillin and a proton pump inhibitor like omeprazole for effective eradication of the bacterium. Metronidazole is also used in H. pylori treatment regimens, but clarithromycin is more commonly preferred. Azithromycin is not typically used for H. pylori eradication. Omeprazole is a proton pump inhibitor that helps reduce stomach acid but is not directly used to treat the infection itself.

Correct Answer: B

Rationale: The correct answer is B: Inhibiting osteoclast-mediated bone resorption. Denosumab is a monoclonal antibody that works by inhibiting osteoclast activity, thereby reducing bone resorption. Osteoclasts are responsible for breaking down bone tissue, so inhibiting their function helps to prevent bone loss in conditions like osteoporosis. Choices A and C are incorrect as denosumab does not directly increase bone formation or promote osteoblast activity. Choice D is also incorrect as denosumab does not affect calcium absorption in the intestines.

Correct Answer: A

Rationale: The correct answer is A: Relaxing vascular smooth muscle, leading to vasodilation. Hydralazine is a direct-acting vasodilator that relaxes arterial smooth muscle, resulting in vasodilation, which decreases systemic vascular resistance and blood pressure. This mechanism of action makes it beneficial in conditions like hypertension and heart failure. Choice B is incorrect as hydralazine does not block beta-1 adrenergic receptors in the heart. Choice C is incorrect because hydralazine does not inhibit the action of aldosterone. Choice D is incorrect as hydralazine does not directly affect the excretion of sodium and water in the kidneys.

Correct Answer: A

Rationale: The correct answer is A: Sumatriptan. Sumatriptan is a triptan medication that works by constricting blood vessels in the brain, reducing inflammation and pain associated with migraines. It specifically targets the serotonin receptors, which helps alleviate migraine symptoms. Aspirin (choice B) and Ibuprofen (choice D) are nonsteroidal anti-inflammatory drugs that do not directly target blood vessels in the brain like Sumatriptan. Propranolol (choice C) is a beta-blocker used for migraine prevention, not for treating acute attacks by constricting blood vessels.