Answer: Option C
Supervision : the action of supervising someone or something.
Co-operation : the action or process of working together to the same end.
Assistance : the action of helping someone by sharing work.
Disease : a disorder of structure or function in a human, animal, or plant, especially one that produces specific symptoms or that affects a specific location and is not simply a direct result of physical injury.
Aid : help, typically of a practical nature.
Synonym of Aid is Assistance