Final answer:
The best window settings for liver tissue differentiation are a WW of 140 and a WL of 60, which provide a good balance to accurately represent variations in tissue density.
Step-by-step explanation:
The question is regarding the optimal window width (WW) and window level (WL) settings for the best tissue differentiation within the liver during imaging. These settings are crucial as they define how the shades of gray will represent various tissues on the image, highlighting the differences among them. When it comes to liver imaging, softer tissues require narrower windows. Out of the provided options, the setting with a WW of 140 and a WL of 60 offers the most appropriate balance to differentiate tissues within the liver due to the modest width allowing for shades of gray to accurately represent variations in tissue density.