It has been said that eye movements are windows into the mind, because where people look reveals what environmental information they are attending to. However, there is more to attention than just moving the eyes to look at objects.
(A)
You may have had this experience if you have been reading a book and then suddenly become aware that although you were moving your eyes across the page and “reading” the words, you had no idea what you had just read.
(B)
Even though you were looking at the words, you apparently were not paying attention. There is a mental aspect of attention that involves processing that can occur independently of eye movements.
(C)
We can pay attention to things that are not directly in our line of vision, as evidenced by the basketball player who dribbles down court while paying attention to a teammate off to the side, just before she throws a perfect pass without looking. We can also look directly at something without paying attention to it.