A test that evaluates lung function by asking the patient to breathe into a device is

• A. X-ray
• B. Pulmonary Function Test
• C. Ultrasound
• D. CT Scan

Answer: (B)

Testing how the lungs work by having the patient breathe into a device focuses on measuring airflow and lung volumes, which is what a pulmonary function test does. The most common method within this testing is spirometry, where a person blows into a mouthpiece connected to a spirometer to quantify how much air they can exhale and how fast. This provides numbers like FVC and FEV1 that help differentiate obstructive from restrictive lung problems. Imaging tests such as X-ray, ultrasound, or CT scan visualize anatomy or pathology but don’t quantify real-time breathing function the way spirometry does. So, the test described is a Pulmonary Function Test.