Ordinary Portland cement should have surface area not less than (in m2/kg) -

Correct option is A

The surface area of Ordinary Portland Cement (OPC) is an important parameter as it determines the rate of hydration and strength development. As per IS 269:2015 (Indian Standard Specification for Ordinary Portland Cement), the minimum specific surface area for OPC should not be less than 225 m²/kg when tested by the Blaine’s air permeability method.