Which medication is given to help with hypertension and preventing angina?

Clonidine is a central alpha agonist that helps manage hypertension by acting on receptors in the brain to decrease sympathetic outflow, resulting in lower heart rate and blood pressure. In addition to its antihypertensive properties, clonidine is sometimes used in the management of certain cases of angina by reducing the heart's workload and oxygen demand, which can alleviate chest pain associated with angina.

Furosemide is a diuretic primarily used to treat fluid retention in conditions such as heart failure, while also indirectly helping in hypertension management by promoting fluid loss. Bismuth subsalicylate is an antidiarrheal medication that does not have a role in treating hypertension or angina. Sildenafil, known for its use in erectile dysfunction, can have a vasodilatory effect but is not typically used to treat hypertension or to prevent angina as its primary indication. Clonidine stands out as the appropriate choice due to its direct effects on both hypertension and angina.