Correct option is C
As per IS 456:2000, the minimum grades of concrete for different types of structures are specified to ensure sufficient strength and durability:
1. Plain Cement Concrete (PCC):
The minimum grade for PCC is M 15. This grade is used for non-reinforced applications such as flooring, levelling courses, and simple foundations.
2. Reinforced Cement Concrete (RCC):
The minimum grade for RCC is M 20. This is because RCC structures are subjected to significant loads and stresses, requiring higher strength and durability.
