The correct option is B It is the highest for objects in solid state.
The speed of a sound wave depends on the characteristics of the medium of propagation. It is the highest in denser media like solids. Hence, when sound travels from solids to liquids or gaseous medium, its speed decreases.
Sound travels at 343 m s−1 in air; it travels at 1,484 m s−1 in water (4.3 times as fast as in air) and at 5,120 m s−1 in iron (about 15 times as fast as in air) .