Which is the best explanation for how earthquakes cause tsunamis? a. Earthquakes shift the seafloor upward or downward, causing water to be vertically displaced. b. Earthquakes shake the water, causing the ripples to move outward in all directions. c. Earthquakes heat ocean water, causing it to expand and move as a wave. d. Earthquakes transmit seismic waves, especially s-waves, upwards through the seawater and when the seismic waves reach the surface, they release that energy in the form of water waves.