Answer: d. Felsic from bottom to top
Explanation:
Most of the known volcanoes are Stratovolcanoes. They are also called Composite volcanoes because they are structured from layers of materials such as lava, ash and tephra that came out during their eruption with each eruption adding more layers than the last.
The lava that flows from a Stratovolcano is usually made up of Felsic along with lesser amounts of silica and mafic. As a result, most of the rocks that make up such volcanoes are Felsic.
