Which of the following is a primary indication of beta-blockers?

Beta-blockers primarily serve as a treatment for hypertension, making this option the correct choice. These medications work by blocking beta-adrenergic receptors, which reduces heart rate and the force of contraction in the heart. This action leads to a decrease in cardiac output and, subsequently, a reduction in blood pressure.

In addition to their role in managing hypertension, beta-blockers are also used for other conditions such as angina and certain arrhythmias, as well as for heart failure management. However, their primary indication remains the treatment of high blood pressure.

While hypotension might seem relevant, beta-blockers would not be used to treat this condition—instead, they are contraindicated if a patient is experiencing low blood pressure. Asthma is generally a concern with beta-blocker use since non-selective beta-blockers can exacerbate bronchospasm; therefore, they are often avoided in asthmatic patients. Hyperthyroidism can also be managed with beta-blockers for symptom control (like tachycardia), but it is not considered a primary indication for their use. Hence, hypertension remains the key and primary condition treated with beta-blockers.