Answer:
C) most of the muscle's energy is produced in mitochondria.
Explanation:
The activities such as running a marathon require aerobic endurance to allow prolonged and sustained muscle contraction for a longer duration (few hours) without fatigue. These activities rely on the production of ATPs in mitochondria through the process of anaerobic cellular respiration.
The process of aerobic cellular respiration produces a large number of ATPs to sustain prolonged muscle contraction. Slow oxidative muscle fibers that contain a large amount of myoglobin and are rich in mitochondria are involved in such activities.