The surface of earth is a thin, solid crust enclosing a molten core of lava. when the core moves, it disturbs the crust at specific locations, which causes earthquakes. how is an earthquake felt on the crust?
a) an explosion that ruptures earth’s surface
b) up-down or sideways wave-like shaking motion
c) the widening of large cracks or fissures over the years
d) a bulging of the ground that takes place over a few days