The speed at which seismic waves travel depends on the properties of the material that they are passing through. For example, the denser a material is, the faster a seismic wave travels. P waves can travel through liquid and solids and gases, while S waves only travel through solids.
I believe the correct answer would be P waves, S waves, L waves. P waves are the first to arrive at a seismic section. S waves move quickly, but not as quick as the P waves, and the L waves are the slowest out of all of them. Hope this helped!
