The correct answer is A. rock minerals.
Sand is a granular material composed of finely divided rock and mineral particles. The particles of sand are larger than silt but smaller than gravel. Sand is typically made up of quartz, feldspar, and other minerals. It can also contain organic matter, such as shell fragments or plant material.
Rock minerals are the basic building blocks of rocks. They are formed when molten rock cools and solidifies. There are many different types of rock minerals, but some of the most common include quartz, feldspar, and mica.
Kaolinite, illite, and montmorillonite are all clay minerals. They are formed when rocks are weathered and broken down. Clay minerals are very fine-grained and have a sheet-like structure. They are used in a variety of products, including ceramics, paper, and cosmetics.
In conclusion, sand particles are made of rock minerals. Rock minerals are the basic building blocks of rocks. They are formed when molten rock cools and solidifies. There are many different types of rock minerals, but some of the most common include quartz, feldspar, and mica.