Correct answer = A.
<p>  Elastic recoil is that property of the
     lung which opposes alveolar distension and which ultimately
     limits TLC in normal individuals.  Smoking leads to tissue
     destruction and loss of elastance (as in emphysema) such that
     there is loss of the tethering forces, which normally keep
     small airways open during expiration, leading to expiratory
     airflow limitation.  Elastic recoil is increased in IPF
     resulting in diminished TLC (i.e. restrictive lung disease).