The nurse documents vital signs on a newly admitted patient as: "blood pressure is 170/90 mm Hg, the pulse is 80 beats/min, and the respirations are 16 breaths/min." The nurse would record the pulse pressure as:

A. Pulse oximetry works by using light absorption to measure the oxygen saturation of hemoglobin in the blood, which typically occurs through the capillary bed in areas like the finger or earlobe.
B. The pulse oximeter does not measure the amount of blood passing through the sensor directly, but rather the oxygen content of the blood.
C. The pulse oximeter does not assess the warmth of the skin as a mechanism for measuring oxygenation.
D. Pulse oximeters measure oxygen saturation levels, not the respiratory rate or blood pressure.

A. Rinsing the thermometer with water is not necessary to ensure an accurate reading. The thermometer should be cleaned after use but rinsing with water does not directly ensure accuracy.
B. Using a dry cotton ball to dry the thermometer is unnecessary and could leave fibers on the device that may interfere with reading accuracy.
C. Wiping the thermometer with alcohol helps sanitize it but does not directly influence the accuracy of the reading.
D. Shaking down the galinstan alloy to below normal is necessary to reset the thermometer before use, ensuring that the mercury level is accurate when taking a new temperature.