$\beta$ -Adrenergic Agonists and Methylxanthines Are Often Prescribed for a Child

$\beta$ -Adrenergic agonists and methylxanthines are often prescribed for a child with an asthma attack. What is their action?

A) Liquefy secretions
B) Dilate the bronchioles
C) Reduce inflammation of the lungs
D) Reduce infection