Initial management of the acute asthma exacerbation includes:

Correct Answer: A

Rationale: First-line treatment for acute asthma exacerbations includes oxygen, nebulized β2 agonists (albuterol), and systemic corticosteroids. Aminophylline and magnesium sulfate are reserved for severe, refractory cases.

Correct Answer: C

Rationale: Early onset is typically associated with a worse prognosis.

Correct Answer: D

Rationale: Methylxanthines decrease pulmonary vascular resistance, not increase it. The other options are therapeutic effects of methylxanthines.

Correct Answer: B

Rationale: Doxorubicin is a chemotherapeutic agent known for its dose-dependent cardiotoxicity, leading to dilated cardiomyopathy due to mitochondrial dysfunction and oxidative stress in cardiac myocytes.

Correct Answer: C

Rationale: Congenital glaucoma typically presents with cloudy corneas and increased intraocular pressure, not leukokoria. The other conditions can cause a white pupillary reflex.