Which imaging technology is part of radiology and uses ionizing radiation?

The choice of a CT scan as the correct answer stems from its foundational use of ionizing radiation in medical imaging. CT, or computed tomography, generates cross-sectional images of the body by combining multiple X-ray views taken from different angles. The ionizing radiation is necessary for producing detailed images of internal structures, allowing for clearer identification of conditions such as tumors, trauma, and internal bleeding.

In contrast, ultrasound employs sound waves to produce images of organs and structures within the body, completely bypassing the use of ionizing radiation. Similarly, nuclear magnetic resonance, which is more commonly known as MRI (magnetic resonance imaging), utilizes strong magnetic fields and radio waves to create detailed images of internal organs, again avoiding ionizing radiation. Therefore, when identifying an imaging technology that specifically involves ionizing radiation, the CT scan stands out as the only valid choice among the options provided.