Montelukast sodium belongs to which of the following therapeutic class(es)?

A. Montelukast sodium is classified as a leukotriene receptor antagonist. It selectively binds to cysteinyl leukotriene type 1 receptors to inhibit physiological effects of leukotrienes. This prevents airway edema, smooth muscle contraction, and inflammatory responses in asthma and allergic rhinitis. B. This agent is not a primary COPD agent as it does not sufficiently address the fixed airflow obstruction or chronic bronchitis characteristic of that disease. While it has antiallergy properties, it is not indicated as a first-line treatment for COPD. C. While montelukast is an antiasthmatic, it is not FDA-approved as a primary COPD agent. Guidelines for chronic obstructive pulmonary disease prioritize long-acting bronchodilators and muscarinic antagonists over leukotriene modifiers. It lacks efficacy in treating non-allergic chronic obstructive lung pathologies. D. Montelukast is an antiallergy medication, but it possesses no antiviral activity. It does not inhibit viral replication, entry, or protein synthesis within host cells. It is exclusively used for managing inflammatory airway diseases and is never indicated for viral infections.