A 66-year-old ex-smoker with GOLD stage 2 COPD has had two exacerbations in the last year despite regular tiotropium (LAMA). According to NICE guideline NG115, what is the next inhaled therapy step?AAdd a long-acting β2-agonist (LABA) in combination with an inhaled corticosteroid (ICS)BSwitch to short-acting β2-agonist monotherapyCAdd a phosphodiesterase-4 inhibitorDStart oral theophyllineERefer immediately for lung volume reduction surgeryCheck my answer