For intake and output, what device should you use to measure fluid output?

Using a graduated cylinder to measure fluid output is appropriate because it provides a precise and accurate measurement. Graduated cylinders are designed with marked increments that allow caregivers to see the exact volume of liquid, which is essential for monitoring a patient’s fluid balance accurately. This level of precision is particularly important in a healthcare setting where even small variations in fluid intake and output can significantly impact a patient's health.

On the other hand, while a measuring cup may offer some utility for basic fluid measurements, it typically is not as precise as a graduated cylinder, especially if the measurements need to be observed in smaller increments. An unmarked container poses significant limitations as it lacks any measurement markings, making it impossible to provide an accurate quantification of the fluid output. Therefore, for tasks requiring careful monitoring, the graduated cylinder is the best choice.