Which code segment correctly displays images with 80% transparency and a blue 8px shadow?

The correct segment is D: filter: opacity(20%) drop-shadow(8px 8px blue);. The requirement says the image must have 80% transparency, which means only 20% opacity remains visible. The CSS filter property applies graphical effects to rendered elements, including image effects such as opacity adjustment and drop shadows. The opacity() filter function is valid inside filter, and values below 100% make the rendered element more transparent. The drop-shadow() function is also a valid CSS filter function and applies a shadow effect to the input image. Option A changes saturation, not transparency. Option B also changes saturation and incorrectly attempts to use box-shadow() as a filter function. Option C uses opacity(80%), which would produce 80% opacity rather than 80% transparency, and it also uses invalid box-shadow() syntax inside filter. References/topics: CSS filter property, opacity(), drop-shadow(), image effects, transparency.

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