The correct answer is D. Granite.
A polymineralic rock is a rock that is composed of more than one mineral. Granite is a type of igneous rock that is composed of three main minerals: quartz, feldspar, and mica. Quartz is a hard, white or clear mineral that is the most common mineral in the Earth’s crust. Feldspar is a group of minerals that are typically white, pink, or gray. Mica is a group of minerals that are typically black, brown, or green.
Quartz sand is a type of sedimentary rock that is composed of mostly quartz grains. Pure gypsum is a type of sedimentary rock that is composed of mostly gypsum. Magnesite is a type of metamorphic rock that is composed of mostly magnesite.
Quartz sand, pure gypsum, and magnesite are all monomineralic rocks, which means that they are composed of only one mineral. Granite is a polymineralic rock because it is composed of more than one mineral.