What does the speed of sound increase through compared to air?

The speed of sound is significantly greater in water compared to air due to the physical properties of the medium. Sound travels through a medium as a pressure wave, and its speed is influenced by factors such as density and elasticity. Water is denser than air, but its particles are also more tightly packed, allowing sound waves to transmit energy more efficiently.

In contrast to air, which has low density and lower bulk modulus (a measure of a material's resistance to deformation), water's higher density and greater elasticity result in faster sound propagation. This principle holds true when comparing other options such as wood, plastic, and glass; while sound speed can also be high in these materials, the specific comparison focuses on the differences between air and water, making water the best answer in terms of facilitating the highest speed of sound among the various options provided.