A. The astenosphere is denser than the lithosphere
Explanation:
The theory of isostasy is a theory that suggest that the layers of Earth are arranged in accordance to their density. It is a theory that usually refers to the mantle and crust. The mantle (astenosphere) is denser than the crust (lithosphere), so the crust floats on top of it, depending on its density, with he continental crust being higher, while the oceanic crust being lower. The two forces that are responsible for this are the gravity and buoyancy.
