What is the best description of the paths of S waves and P waves? S waves travel through solids or very dense, glassy liquids. P waves travel through solids, liquids, and gasses. S waves travel through solids, liquids, and gasses. P waves travel through solids or very dense, glassy liquids. S waves travel through Earth's interior. P waves travel along the surface of Earth's crust. S waves travel along the surface of Earth's crust. P waves travel through Earth's interior.