A 5-year-old boy is brought to the physician by his parents for poor motor development. He has a waddling gait and enlargement of the calf muscles. He has difficulty standing up from a seated position on the floor and uses his arms to support himself. Serum CK is elevated. Which of the following is most likely to be seen in this patient?
AR disorder; decreased muscle length of individual muscle fibers
AR disorder; increased muscle bulk caused by muscle cell hypertrophy
AR disorder; replacement of muscle cells by connective tissue stromal cells
AD disorder; decreased muscle length of individual muscle fibers
AD disorder; increased muscle bulk caused by muscle cell hypertrophy
AD disorder; replacement of muscle cells by connective tissue stromal cells
XR disorder; decreased muscle length of individual muscle fibers
XR disorder; increased muscle bulk caused by muscle cell hypertrophy
XR disorder; replacement of muscle cells by connective tissue stromal cells
