With regard to minerals, hardness refers to as. the ability to resist being scratched by other substances b. the ability to resist breaking when being struck with a hammer c. the ability to resist chemical reactions with other substances d. an absence of cleavage

The answer is, Hardness brings up to as the ability to resist being scratched by other substances with regards to mineral. The hardness of a mineral is stately in contradiction of the scale by the judgment of the hardest mineral that the given mineral can scratch, and/or the softest material that can scratch the specified mineral. The gradation of hardness is determined through noticing the reasonable affluence or strain which one mineral is scratched by a different one. 

They both have rock surfaces