Final answer:
The pop-out phenomenon demonstrates that certain stimuli can trigger selective attention, as shown by the Invisible Gorilla Experiment where inattentional blindness occurs due to intense focus on a specific task.
Step-by-step explanation:
The pop-out phenomenon illustrates that some stimuli almost inevitably trigger c. selective attention. Selective attention refers to our ability to focus on one particular stimulus while simultaneously ignoring other stimuli. The classic demonstration of this is the Invisible Gorilla Experiment by Simons and Chabris, where participants failed to notice a person in a gorilla suit walking through a basketball passing drill because they were intensely focused on counting the passes of the team in white. This is an instance of inattentional blindness, which is a specific type of selective attention where the failure to notice a fully visible, but unexpected object occurs because one's attention is engaged on another task or aspect of the environment.