Final answer:
Urine that is hyperosmotic contains a small amount of water, implying a high concentration of solutes due to less water being excreted by the kidneys under conditions such as dehydration.
Step-by-step explanation:
Urine that is hyperosmotic contains a small amount of water (C). Hyperosmotic urine has a higher concentration of solutes than the body's fluids. This higher concentration is due to the kidneys excreting less water to conserve it, which leads to more concentrated urine.
During conditions such as dehydration or when the fluid intake is lower, the kidneys concentrate urine to save water, resulting in hyperosmotic urine. Conversely, when there is excess water intake, kidneys will excrete a more dilute urine, making it hypoosmotic.
The osmolality test measures the concentration of dissolved particles and confirms whether the kidneys are concentrating urine properly. If the fluid intake is restricted, the osmolality should be greater than 800 mOsm/kg of water, indicating hyperosmotic urine.