9.下列有關COPD藥物之描述何者錯誤? (A) Some patients with refractory dyspnea will experience improved exercise tolerance with theophylline (B) For patients with recurrent exacerbations (eg, at least two per year or one requiring hospitalization) despite triple inhalers, the phosphodiesterase-4 inhibitor roflumilast may reduce the frequency of exacerbations (C) For patients with recurrent exacerbations prolonged use of azithromycin may reduce the frequency of exacerbations (D) Azithromycin should be avoided in patients with a short QT interval