A 45-year-old man with a 30-pack-year smoking history is diagnosed with COPD. Spirometry shows FEV1 55% predicted. He is still smoking. Which intervention is most likely to have the greatest long-term impact on disease progression and mortality?AAdding a long-acting beta-2 agonist inhaler.BAdding an inhaled corticosteroid to his regimen.CReferral for pulmonary rehabilitation.DSmoking cessation support including nicotine replacement therapy.EAnnual influenza vaccination alone.Check my answer