The correct answer is c) Limestone.
Limestone is a sedimentary rock composed mostly of calcium carbonate (CaCO3). It is the most common type of limestone and is used in a variety of applications, including the cement industry. Limestone is used in cement because it is a source of calcium oxide (CaO), which is one of the main ingredients in cement. Calcium oxide reacts with silica (SiO2) and alumina (Al2O3) to form calcium silicate hydrate (C-S-H), which is the main binder in cement.
Iron ore is a mineral that is used to make iron and steel. It is a primary source of iron, which is the main component of these metals. Iron ore is found in a variety of forms, including hematite, magnetite, and taconite.
Granite is an igneous rock that is composed of quartz, feldspar, and mica. It is a hard, durable rock that is used in a variety of applications, including construction, countertops, and monuments.
Sand is a granular material composed of finely divided rock and mineral particles. It is used in a variety of applications, including construction, glassmaking, and abrasives.