Which of the following describes a positron emission tomography (PET) scanner? 1: A device that uses magnetic fields to produce images of brain structures 2: A device that uses magnetic fields to measure blood flow 3: A device that uses radioactive fluid to determine the active areas of the brain 4: An X-ray device that can create a 3D model of the brain

3: A device that uses radioactive fluid to determine the active areas of the brain

Explanation:

A positron emission tomography (PET) scan is an imaging test that helps reveal how your tissues and organs are functioning. A PET scan uses a radioactive drug (tracer) to show this activity. This scan can sometimes detect disease before it shows up on other imaging tests.

Depending on the type of exam, the radiotracer is injected, swallowed or inhaled as a gas. It eventually accumulates in the area of the body under examination. A special camera or imaging device detects radioactive emissions from the radiotracer. The camera or device produces pictures and provides molecular information.

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explanation:

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