Which Photoshop feature allows for non-destructive editing?

Using adjustment layers is the feature in Photoshop that facilitates non-destructive editing. Adjustment layers enable users to apply color and tonal adjustments to their images without altering the original pixel data. This means that you can modify or completely remove these adjustments at any time, allowing for flexible and reversible edits. By using adjustment layers, you can fine-tune settings like brightness, contrast, hue, saturation, and more, while preserving the original image layer untouched.

The other options, such as flattening layers, create a merged version of all layers, which permanently applies all edits and prevents any further modification without starting over. Creating a new action allows you to automate processes, but it doesn't inherently support non-destructive editing. Changing image resolution adjusts the size and details of the image, which can also lead to loss of quality and destruction of pixel data. Hence, adjustment layers stand out in promoting a workflow that retains the ability to revert to previous edits at any time.