Arformoterol belongs to which of the following therapeutic drug class(es)?

A. Arformoterol is indicated for the long-term maintenance treatment of bronchoconstriction in patients with chronic obstructive pulmonary disease. It acts as a long-acting beta-2 adrenergic agonist to improve forced expiratory volume. This clinical application defines its classification. B. This drug lacks activity on the cough reflex center in the medulla oblongata. It does not possess the pharmacological properties of peripheral or central antitussives like codeine or dextromethorphan. It is not used to suppress non-productive cough. C. Arformoterol does not antagonize H1 receptors or inhibit the release of histamine from mast cells. Its mechanism of action is independent of the inflammatory pathways targeted by antihistamines. It serves no role in treating allergic rhinitis or urticaria. D. As the (R,R)-enantiomer of formoterol, it stimulates adenylate cyclase to increase intracellular cyclic adenosine monophosphate levels. This process leads to the relaxation of bronchial smooth muscle cells. The resulting increase in airway caliber defines it as a bronchodilator.