Which of the following pulmonary function tests involves ves measuring the oxygen saturation of a patient's blood by placing a probe on their finger? Pulse oximetry Peak flow monitor Spirometry test Lung volume test

## Step 1<br />The question is asking us to identify the type of pulmonary function test that involves measuring the oxygen saturation of a patient's blood by placing a probe on their finger. <br /><br />## Step 2<br />Pulse oximetry is a non-invasive method used to measure the oxygen saturation level in the blood. It works by passing light through a body part, such as a finger, and then measuring the amount of light absorbed by oxygenated and deoxygenated blood. The device then calculates the percentage of oxygen-saturated blood.<br /><br />## Step 3<br />The other options, Peak flow monitor, Spirometry test, and Lung volume test, are also types of pulmonary function tests, but they do not measure the oxygen saturation of a patient's blood by placing a probe on their finger.