Which option defines the action of cropping an image?

Cropping an image refers specifically to the process of removing unwanted parts of the image to improve framing, focus on elements of interest, or alter the composition. By cropping, you can eliminate distractions, enhance the visual impact, and create a more balanced aesthetic. This is an essential technique in graphic design and photography that allows the designer to control the viewer's attention and compositional elements effectively.

In contrast, adjusting brightness and contrast involves modifying the tonal range in an image to improve visibility and detail but does not physically change the image's dimensions or composition. Adding a border is a decorative element that surrounds the image rather than altering its internal content. Compressing the image pertains to reducing the file size for storage efficiency, which also does not involve changing the visible aspects of the image itself. Thus, the action of cropping is uniquely defined by the removal of unwanted areas within the image.