Question

a mad scientist sees waves travel through solid but not liquid layers of earth. which waves are missing in the core? s - waves sound waves p - waves surface waves

Explanation:

S - waves (secondary waves) are a type of seismic wave that can only travel through solid materials and cannot travel through liquid. The Earth's outer core is liquid, so S - waves are missing (cannot propagate) in the core. Sound waves are a general type of wave that can travel through different media depending on the medium, and this is not the key here. P - waves (primary waves) can travel through both solids and liquids. Surface waves travel along the Earth's surface. So the waves missing in the core (due to the core's liquid part) are S - waves.

Answer:

A. S - waves