Answer:
The correct option is Option C
i.e. Asthenosphere is denser than lithosphere.
Step-by-step explanation:
Asthenosphere is the layer situated below the lithosphere.
Theory of isostasy says that the layers above the other layer must have lesser density. This has two explanations. Firstly, if its not hold, then the denser above layer would sink below the less denser bottom layer. Secondly, as we go inwards, the pressure increases. This leads to the lower layers have greater density. So, as Asthenosphere is situated below the lithosphere, it has higher density.