A 7-year-old boy with no prior respiratory disease presents to the emergency department with acute onset dyspnea and bilateral wheezing that began 10 minutes after sprinting during a soccer game on a cold, dry day. He denies fever, cough, or recent upper respiratory infection. Physical examination reveals clear bilateral wheezing, prolonged expiratory phase, and peak expiratory flow of 62% predicted. Oxygen saturation is 94% on room air. He receives nebulized albuterol and shows rapid clinical improvement with normalization of peak flow to 88% predicted within 30 minutes. Which of the following is the most likely diagnosis?

1. A)Acute viral bronchitis with reactive airway disease
2. B)Exercise-induced bronchoconstrictionGABARITO
3. C)Acute asthma exacerbation triggered by environmental allergen exposure
4. D)Foreign body aspiration of the left mainstem bronchus
5. E)Anaphylaxis secondary to insect sting during outdoor activity