Which of the following is a primary imaging modality used for soft tissue evaluation?

MRI, or Magnetic Resonance Imaging, is the primary imaging modality used for soft tissue evaluation due to its sensitivity and contrast resolution in depicting soft tissue structures. Unlike X-rays, which primarily visualize bone, and CT scans, which provide detailed cross-sectional images but are less effective for distinguishing between different types of soft tissues, MRI uses strong magnetic fields and radio waves to generate detailed images of soft tissues such as muscles, fat, blood vessels, and organs.

Fluoroscopy, while useful for observing dynamic processes and real-time imaging, does not provide the same level of detail for soft tissue evaluation as MRI. Therefore, MRI is uniquely suited for assessing conditions involving soft tissues, making it the correct choice for this question.