A Chemical rock is: B) a rock formed from precipitation of minerals from solution.
Chemical rocks are formed when minerals precipitate out of a solution, typically through processes such as evaporation or chemical reactions. The minerals crystallize and accumulate to form the rock. Examples of chemical rocks include limestone, gypsum, and rock salt. This is in contrast to clastic rocks (option A), which are formed from the cementation of transported grains. The transformation of rocks by heat (option C) or pressure (option D) into limestone is not characteristic of chemical rocks.