3. "The mantle rock close to the center of the earth is... a) cold.
b) hot.
c) frozen
d) sinking

The crust and the upper layer of the mantle together make up a zone of rigid, brittle rock called the Lithosphere . The layer below the rigid lithosphere is a zone of asphalt-like consistancy called the Asthenosphere . The asthenosphere is the part of the mantle that flows and moves the plates of the Earth.

Explanation:

so i think its b.) im so sorry if im wrong have a wonderfull day <3

answer; (d) melting of sea ice;