ANS:B - Diamond

Among the options provided, diamond has the highest value of refractive index. The refractive index is a measure of how much light bends or refracts as it passes from one medium to another. It is defined as the ratio of the speed of light in a vacuum to the speed of light in the medium. The higher the refractive index, the more the light is bent when it enters the medium. Diamond has an exceptionally high refractive index of approximately 2.42, making it one of the most optically dense materials known. This property contributes to diamond's brilliance and sparkle, as it bends and disperses light very effectively. In comparison:

• Glass typically has a refractive index ranging from about 1.4 to 1.7.
• Distilled water has a refractive index of approximately 1.33.
• Brine (sea water) has a refractive index slightly higher than distilled water, but still lower than that of diamond.