SSC MTS 2024 PYQ — Question 54

The correct answer is option 4 i.e.  lithosphere. 

All natural earthquakes originate in the lithosphere, the rigid outer layer of the Earth that includes the crust and the uppermost mantle.

Earthquakes occur due to the sudden release of built-up stress along geological faults or fractures in the lithosphere, where tectonic plates interact.

While the asthenosphere (a softer, flowing layer beneath the lithosphere) facilitates plate movements, it does not generate earthquakes directly due to its ductile nature.

The hydrosphere (water bodies) and biosphere (living organisms) are affected by earthquakes but are not their source. Thus, the lithosphere is the primary domain for seismic activity.