Scientists use the properties of seismic waves to figure out the structure of Earth's interior. For example, seismic waves travel faster through denser layers than through less dense layers. Also, P waves can travel through both solids and liquids, but S waves can travel through solids only.

Because P and S waves travel faster through the Earth's mantle than through Earth's crust, scientists know that the mantle is _______ and _______ than the crust.
A.
liquid; less dense
B.
solid; less dense
C.
solid; denser
D.
liquid; denser

1 answer

The correct answer is C. solid; denser.

P waves and S waves travel faster through the Earth’s mantle than through the crust, indicating that the mantle is denser and solid compared to the crust, which is less dense.