Which of the following is a risk associated with working on a computer?

Back strain is a common risk associated with working on a computer, particularly due to prolonged periods of sitting in front of a screen. Many individuals often adopt poor posture while seated or do not have ergonomically designed furniture, which can lead to tension and discomfort in the back muscles. This strain can result from inadequate lumbar support, screen height not being adjusted properly, or not taking regular breaks to stand and stretch.

In the context of the other options, while fatigue from standing too long can certainly be an issue in different work environments, it does not specifically pertain to computer use. Noise pollution generally relates to external disturbances rather than the act of working on a computer. Insufficient lighting can contribute to eye strain rather than back strain directly, which makes back strain the more immediately relevant concern in this scenario.