Final answer:
The depth cue illustrated in this scenario is called binocular disparity, which is the slightly different view each eye has of an object. It helps the brain determine depth.
Step-by-step explanation:
The depth cue illustrated in this scenario is called binocular disparity. When you hold your right index finger two feet in front of your face and alternate between closing one eye and then the other, you'll notice that your finger appears to jump back and forth. This is because each eye has a slightly different view of your finger, and your brain uses these differences to determine depth.