The answer is C. Repetitive motion develops nerves and nerve endings. Nerves have neurons, neurons have receptors. When we exercise, the neurons in the nerves gets activated and opens up the receptors which in turn helps in developing the nerves. For example. if you have a serious muscle cramp the nerve gets affected by it and gets weaker. Then when you do physiotherapy regularly it slowly gets cured as it unblocks the nerve and develops it.
