Which of the Following Is Not a Reason Muscular Weakness

Which of the following is not a reason muscular weakness tends to develop in old age?

A) Aged muscle has less glycogen,myoglobin,and creatine phosphate.
B) There are fewer motor neurons in the spinal cord.
C) Aged muscle fibers have fewer myofibrils.
D) There are fewer and smaller mitochondria in aged muscle.
E) The myocytes of aged muscle no longer synthesize myosin.