What are the 20 minerals that make up most of the rocks of earths crust are known as?

For example, the granite in Figure 2 is made up of the minerals quartz, feldspar, hornblende, and mica. About 20 minerals make up most of the rocks of Earth's crust. These minerals are known as rock-forming minerals. Appendix B at the back of this book lists some of the most common rock forming minerals.

Don't depend on this but logically i think c