What is an adjustment layer and why is it preferred over direct image adjustments?

What is an adjustment layer and why is it preferred over direct image adjustments?

• A. It permanently changes pixel values on the layer.
• B. It only affects text layers.
• C. It requires flattening the image before edits.
• D. An adjustment layer applies color/tonal changes non-destructively and can be masked or edited without altering the original pixels.

Answer: (D)