Concept:The speed of a sound wave depends on the properties of the material through which it travels.
Explanation:Sound requires a medium such as air, water, or solid to travel.
Its speed is mainly determined by the density and elasticity of the medium.
Temperature also affects speed, since sound travels faster in warmer media.
However, amplitude, intensity, and loudness only affect how the sound is perceived or its energy, not its speed.
Therefore, the key factor is a property of the medium itself.
Answer:A. properties of the medium