Final answer:
The seismic wave that passes through the Earth's liquid outer core is the P-wave or pressure wave, which is a longitudinal wave that can travel through both solids and liquids.
Step-by-step explanation:
The type of seismic wave that can pass through the liquid outer core of the Earth is the P-wave, also known as a pressure wave or a longitudinal wave. S-waves, or shear waves, cannot travel through liquids and therefore do not pass through the outer core.
R-waves and L-waves are types of surface waves and are not typically used to describe waves that travel through the interior of the Earth.
Understanding the behavior of seismic waves is crucial for studying the structure of the Earth's interior. P-waves are faster and can travel through both solid and liquid materials, which is why they are able to pass through the liquid outer core.
The inability of S-waves to travel through the outer core creates a seismic shadow zone, which helped in the discovery of the liquid nature of the outer core.