Which region is beneath the lithosphere and allows the transmission of transverse seismic waves?

The asthenosphere is a layer located beneath the lithosphere, characterized by its partially molten rock that is capable of flowing. This property is crucial for the transmission of seismic waves. Unlike the rigid lithosphere, which can support the propagation of seismic waves, it is the asthenosphere that specifically allows transverse seismic waves, or S-waves, to travel through it.

Transverse seismic waves require a certain level of fluidity to propagate effectively. The partially molten state of the asthenosphere means that it is less rigid than the lithosphere, enabling these waves to move through. The lithosphere above is too solid and brittle, which affects the transmission of different types of seismic waves.

The other regions mentioned do not have the same characteristics. The continental crust is a solid layer that does not allow for the same type of wave movement. Fault lines may be associated with seismic activity but are locations of fractures rather than distinct layers of material. The mesosphere, deeper within the Earth, is more rigid than the asthenosphere, making it less conducive to the transmission of transverse waves. Thus, the asthenosphere plays a critical role in supporting the movement of these seismic waves due to its unique properties.