Bronchial hyperplasia may be caused by all except?

Answer is B (Theophylline): Theophylline relaxes the tone of bronchial smooth muscles, thereby causing bronchodilation It may he used in the treatment of bronchial hyperplasia, it ceainly does not contribute to bronchial hyperplasia. Smoking and other irritants cause the hyperophy of mucus glandsQ within the brochial wall, and contributes to narrowing of bronchioles by a variety of factors. Prematurity may be associated with bronchopulmonary dysplasiaQ and bronchial hyperplasiae