The speed of sound in water is approximately 1500 meters per second (m/s) at room temperature.
Based on the options provided, none of them accurately reflect the typical speed of sound in water. However, if you have to choose the closest one, option d. 2000 m/sec is the most appropriate, although it's still an overestimate.
So, the correct choice among the given options is d. 2000 m/sec.