Which physical layer of earth is broken into tectonic plates?

The lithosphere is the physical layer of Earth which is broken into tectonic plates.  

Lithosphere is the rigid outermost layer of the Earth's crust. It is composed of the crust as well as the upper part of the mantle.

There are two types of lithospheres:
1- A type associated with oceans called "Oceanic lithosphere" with density about 2.9 gm/cm^3
2- A type associated with land called "Continental lithosphere" with density about 2.7 gm/cm^3

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