How Do Corticosteroids Improve Breathing in Patients with Asthma or Chronic

How do corticosteroids improve breathing in patients with asthma or chronic obstructive pulmonary disease (COPD) ?

A) Relaxing bronchial smooth muscle,leading to wider airways
B) Reducing mucosal swelling in the lumens,leading to wider airways
C) Triggering the sympathetic nervous system,leading to deeper respirations
D) Controlling anxiety,leading to an increased ability to focus on respiratory effort