Final answer:
Subject contrast in radiography typically increases with adjacent body parts that have significantly different tissue types or densities, aiding diagnostic interpretation.
Step-by-step explanation:
In medical imaging, particularly in radiography, subject contrast refers to the difference in brightness between adjacent areas on an image. Subject contrast between adjacent body parts typically increases as the difference in the types of tissues or their density becomes more significant because different tissues absorb X-rays to different extents. For instance, bone and soft tissue will have high contrast due to their different absorption rates, whereas two different types of soft tissue may have a lower contrast. Knowledge of subject contrast is essential for diagnostic purposes and plays a crucial role in interpreting radiographs.