Final answer:
The correct RPMs for centrifuging a urine sample is typically 1000 to 2000 rpms (option c). This speed is adequate for sedimenting cells without damaging them, while higher speeds indicated in other options could disrupt the sample integrity.
Step-by-step explanation:
The correct setting for the centrifuge RPMs (rotations per minute) for a urine sample is typically between 1000 to 2000 rpms. Option (c) is the most common range used in laboratory settings for the centrifugation of urine samples. This speed is sufficient to sediment cells and other particulates without causing damage to the cells or risking the disruption of the sample integrity.
While options a (6000 to 7000 rpm), b (4000 to 5000 rpm), and d (3000 to 4000 rpm) could potentially be used for other protocols, such as DNA extraction where a microcentrifuge capable of 10,000g might be employed, these settings are too high for processing urine samples. The high-speed options could lead to the breaking of cells and the release of intracellular components, which could interfere with the analysis of the urine sample.