In what medium do P waves travel?

P waves, or primary waves, are a type of seismic wave generated by geological activities like earthquakes. These waves are characterized as longitudinal waves, which means that they cause particles of the medium to move parallel to the direction of the wave's propagation.

P waves are unique in that they can travel through both solids and liquids because they compress and expand the material they move through. This ability to propagate through different states of matter is due to the fact that both solids and liquids have the ability to support the compressional stress that P waves exert.

In contrast, the other options suggest limitations on the propagation of P waves. For instance, the notion that P waves only travel through solids or only through liquids fails to recognize their capability to traverse multiple types of media. Hence, the correct understanding aligns with the fact that P waves can indeed travel through both solids and liquids, which makes the choice that states this the correct answer. This is an important aspect of seismic wave behavior and is crucial for interpreting data from geological activities such as earthquakes.