Explanation

The speed of sound is greatest in the densest, least compressible medium among the choices. Sound travels faster in liquids than in gases, and within liquids its speed rises with density and bulk modulus. Sea water is denser than distilled water, drinking water or methanol because of its dissolved salts, giving it a sound speed of about 1531 m/s versus roughly 1480 m/s in pure water. Hence option B is correct.