What is the name of the boundary between the lower mantle and the core, characterized by a change in seismic wave behavior?

The boundary between the lower mantle and the core is known as the Gutenberg Discontinuity. This boundary is significant because it marks a drastic change in the materials and characteristics of the Earth's interior. Below this discontinuity, seismic waves behave differently due to the transition from the solid lower mantle to the liquid outer core. The density and composition of materials change considerably at this interface, which affects how seismic waves travel through the Earth.

The other options refer to different seismic boundaries. The Mohorovicic Discontinuity, often called the Moho, is the boundary between the Earth's crust and the underlying mantle, where seismic wave speeds increase significantly due to the transition from less dense rocks of the crust to denser rocks of the mantle. The Asthenosphere Boundary refers to the upper part of the mantle that is partially molten and allows for the movement of tectonic plates. The Mesosphere Boundary typically refers to the region within the mantle itself, specifically between different layers of the mantle. Each of these boundaries has its own unique characteristics that distinguish it from the Gutenberg Discontinuity.