<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 4-year-old boy is brought to the clinic by his mother with a history of multiple falls for the last 8 months. He was born at term without any perinatal complications. At birth, his weight and height were 57th and 62nd percentile for his age, respectively. For the first year, he had normal developmental milestones. He started walking at the age of 17 months and started climbing stairs at 2 years of age. For the last 810 months, he has been walking clumsily, has fallen multiple times, and is having difficulty standing from the sitting position. He is not able to climb the stairs now. Past medical history is unremarkable. His vaccinations are up-to-date. His maternal uncle had a similar history, and he became bed-bound at 12 years of age. During the physical examination, the patient stood up from sitting position slowly by placing hands on his knees. What additional findings will be present in this patient?? A: Early contractures at multiple joints, B: Inability to release grasp after handshake, C: Inverted champagne bottle legs, D: Pseudohypertrophy of the calf muscles, E: Rash over shoulders and anterior chest,  <response>: This is a clinical vignette describing a 4-year-old boy with progressive difficulty walking and falls over the past 8 months. He has lost previously attained motor milestones. There is a family history of a similar condition in a maternal uncle that led to being bedbound by age 12. The description and family history are classic for Duchenne muscular dystrophy. In Duchenne muscular dystrophy, there is progressive proximal muscle weakness and pseudohypertrophy enlargement of the calf muscles. This stems from replacement of muscle tissue with fat and connective tissue. Of the answer choices, pseudohypertrophy of the calf muscles is the classic physical exam finding in Duchenne muscular dystrophy. The other findings would not be expected.D: Pseudohypertrophy of the calf muscles 