What percentage of urine is composed of water?

Urine is primarily composed of water, with a typical composition ranging between 90% to 95%. The correct choice, which states that urine is composed of approximately 95% water, reflects the general understanding of urine's composition in human physiology.

The primary components of urine include urea, creatinine, various ions, and other solutes, all dissolved in water. Since water serves as the major solvent in urine, it is vital for the excretion of waste products from the body and the regulation of fluid balance.

While options suggesting a lower water percentage (80% or 90%) do not accurately capture the higher fluid content of urine, the option stating 100% water is incorrect as it overlooks the presence of various metabolic waste products and solutes in urine. Overall, the established notion is that urine typically contains around 95% water, making that choice the most appropriate answer.