Change blindness is best described as:

Change blindness refers to the phenomenon where an observer fails to notice significant changes in a visual stimulus when it occurs unexpectedly or gradually. This concept highlights the limitations of human attention and perception, illustrating that even though we are constantly surrounded by visual information, our awareness of changes in our environment can be remarkably poor.

The correct description captures the essence of this phenomenon, emphasizing the role of attention in perceiving changes. When individuals are not focused on certain aspects of their visual field, they may completely overlook alterations that could be quite noticeable if they were directly focused on them. This failure to attend to changes occurs even when the changes are significant, reinforcing the idea that our perceptual experience is not a straightforward reflection of reality but is instead shaped by the limits of our attentional capacities.

In summary, the notion that change blindness is a failure to bring attention to changes in our environment accurately encapsulates this psychological concept, demonstrating how our perception is influenced by where we focus our attention.