<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 7-year-old boy is brought to the physician by his mother because of a 2-week history of intermittent shortness of breath and a dry cough that is worse at night. He had an upper respiratory tract infection 3 weeks ago. Lungs are clear to auscultation. Spirometry shows normal forced vital capacity and peak expiratory flow rate. The physician administers a drug, after which repeat spirometry shows a reduced peak expiratory flow rate. Which of the following drugs was most likely administered?? A: Atenolol, B: Methacholine, C: Ipratropium bromide, D: Methoxyflurane, E: Epinephrine,  <response>: This is a clinical vignette about a 7-year-old boy with a 2-week history of shortness of breath and dry cough, worse at night. He had an upper respiratory infection 3 weeks ago. Initial lung exam and spirometry were normal. After administration of a drug, repeat spirometry showed reduced peak expiratory flow rate. The question is asking which drug was most likely administered to cause bronchospasm and reduced peak expiratory flow rate.Methacholine is a drug that can be used to test for bronchial hyperresponsiveness. In patients with asthma, methacholine will cause bronchospasm and reduced peak expiratory flow. The other answer choices would not be expected to cause bronchospasm.B: Methacholine 