<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 55-year-old man is brought to the emergency department by ambulance from a long term nursing facility complaining of severe shortness of breath. He suffers from amyotrophic lateral sclerosis and lives at the nursing home full time. He has had the disease for 2 years and it has been getting harder to breath over the last month. He is placed on a rebreather mask and responds to questions while gasping for air. He denies cough or any other upper respiratory symptoms and denies a history of cardiovascular or respiratory disease. The blood pressure is 13270 mm Hg, the heart rate is 98min, the respiratory rate is 40min, and the temperature is 37.6C 99.7F. During the physical exam, he begs to be placed in a sitting position. After he is repositioned his breathing improves a great deal. On physical examination, his respiratory movements are shallow and labored with paradoxical inward movement of his abdomen during inspiration. Auscultation of the chest reveals a lack of breath sounds in the lower lung bilaterally. At present, which of the following muscles is most important for inspiration in the patient?? A: External intercostal muscles, B: Sternocleidomastoid muscles, C: Muscles of anterior abdominal wall, D: Trapezium muscle, E: Internal intercostal muscles,  <response>: This is a medical question asking about which muscle is most important for inspiration in a patient with amyotrophic lateral sclerosis ALS. The patient has severe breathing difficulties and paradoxical breathing, indicating respiratory muscle weakness. In ALS, the diaphragm and intercostal muscles are affected, leading to impaired inspiration. The description of paradoxical breathing and lack of breath sounds in the bases suggests the diaphragm is very weak. When the diaphragm is weak, the accessory muscles of inspiration like the sternocleidomastoid are recruited to assist with breathing. B: Sternocleidomastoid muscles 