Which of the following conditions could lead to vision issues if left untreated?

Both blepharitis and dry eye syndrome can lead to vision issues if left untreated.

Blepharitis is an inflammation of the eyelid margins, which can cause redness, irritation, and a crusty build-up at the base of the eyelashes. If this condition is not addressed, it can lead to more serious problems, including infections, corneal abrasions, and in some cases, chronic discomfort, which can significantly affect a person's vision.

Dry eye syndrome occurs when there is insufficient tear production or poor tear quality, leading to dryness and irritation of the eye surface. This condition can also lead to complications such as corneal damage and increased risk of eye infections if not properly managed over time. Proper lubrication and treatment are essential to maintain vision health in individuals suffering from dry eye syndrome.

Both conditions highlight the importance of early intervention and management in preserving eye health and preventing potential vision impairments. Thus, the correct answer acknowledges that untreated blepharitis and dry eye syndrome both have the potential to lead to vision issues.