* Sedimentary Rocks: These rocks form from the accumulation and cementation of sediments, which can be fragments of other rocks, minerals, or organic materials.

* Chemical Processes: Rock salt forms when bodies of water evaporate, leaving behind dissolved minerals. The mineral halite (NaCl) crystallizes out of the water, forming layers of salt.

Let's consider the other options:

* Granite: This is an igneous rock, formed from the cooling and solidification of molten rock (magma).

* Basalt: Another igneous rock, formed from volcanic eruptions.

* Quartzite: This is a metamorphic rock, formed when sandstone (a sedimentary rock) is subjected to intense heat and pressure.

Therefore, rock salt is the only option that is both sedimentary and formed through chemical processes.