Correct Response: B. "Placing the screen an arm's length away and slightly below eye level" prevents eyestrain. Focusing on the screen at this distance allows the ciliary muscles, which control the shape of the eyes' lenses, to be at rest. Humans see more visual field below the horizon than above. This is why the screen should be slightly below eye level. A is incorrect because the computer user should take a two-minute break looking into the distance every fifteen minutes, not every 4 hours (A). C is incorrect because bright lighting (C) should be avoided. It can cause glare and increase eyestrain. It also gives the screen a washed out look that makes it more difficult to view. D is incorrect because black print on a white background is the best combination for eye comfort. Light colored print against a white background (D) increases eyestrain.
