Correct Option: D

The Mohorovicic discontinuity, usually referred to as the Moho, is the boundary between the Earth’s crust and the mantle. Named after the pioneering Croatian seismologist Andrija Mohorovicic, the Moho separates both the oceanic crust and continental crust from underlying mantle. The Moho mostly lies entirely within the lithosphere; only beneath mid-ocean ridges does it define the lithosphere – asthenosphere boundary..