Which description is true of earth’s four layers?

The astenosphere is located below the lithosphere

The mantle is composed of silicate material

Explanation:

The Earth has several different layers, and they can be presented in two different manners, depending on their chemical composition and their physical properties. According to the chemical composition the Earth has three layers, crust, mantle, and core, while in accordance to the physical properties it has five, lithosphere, astenosphere, mesosphere, outer core, and inner core.

The astenosphere is the second layer from the top, and it lies just below the lithosphere. It is also the upper part of the mantle. The mantle is a layer that is largely composed of silicate material, mostly silicate molten rock. It can easily be seen from the volcanic activities that this layer is composed of silicate material because the magma is rich in it, and the magma comes from this layer.