C standard

C standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standardC standard