Which description identifies the lithosphere?

Question 3 options:

a.made up of the upper mantle and composed of cool, rigid rocks


b.made up of the upper mantle and composed of rocks that behave like plastic


c.made up of the crust and a portion of the upper mantle and composed of rocks that are rigid


d.made up of the crust and a portion of the upper mantle and composed of rocks capable of gradual flow