Final answer:
A person with renal calculi needs to drink 3 liters or more per day to ensure the production of 2 to 2.5 liters of urine per day and prevent dehydration and the formation of kidney stones.
Step-by-step explanation:
The person with renal calculi is encouraged to drink more fluids to help flush away materials that could form kidney stones and manage hydration levels. When considering the options provided, the most appropriate answer is c) 3 liters or more per day. This recommendation aligns with the preventive strategies to produce 2 to 2.5 liters of urine per day by consuming enough water. It's important to note that while the kidneys can regulate water levels in the body, conserving water if you are dehydrated and making urine more dilute to expel excess water if necessary, the minimum level of urine production necessary to maintain normal function is about 0.47 liters (0.5 quarts) per day. Consuming a lower amount of fluids than needed can lead to oliguria, where urine excretion may be less than 600 ml/day, which could be harmful, especially in the case of renal calculi where regular flushing of the urinary system is necessary.