## Core Concept
Visual acuity development in children is a critical aspect of pediatric ophthalmology. The maturation of the visual system, particularly the development of the fovea and the myelination of the optic nerve, plays a significant role in achieving adult-like visual acuity.

## Why the Correct Answer is Right
The correct answer states that normal resolution visual acuity levels, such as that of adults (i.e., 6/6), is attained by 5 years of age. This is because the visual acuity of children improves significantly over the first few years of life. At birth, the visual acuity is very low, but it rapidly improves. By around 3-4 months, infants can see objects clearly at a distance of about 8-12 inches. By 1 year, the visual acuity is approximately 6/60 to 6/30, and by 3 years, it improves to around 6/20 to 6/30. It continues to refine, and by the age of 5, most children achieve a visual acuity of 6/6, similar to that of adults.

## Why Each Wrong Option is Incorrect
**Option A:** 3 years - This is too early for most children to achieve adult-like visual acuity. At 3 years, the visual acuity is typically around 6/20 to 6/30.

**Option B:** 7 years - This is later than necessary. Most children achieve adult-like visual acuity before this age.

**Option D:** 10 years - This is far beyond the typical age for achieving adult-like visual acuity.

## Clinical Pearl / High-Yield Fact
A key point to remember is that visual acuity in children can be difficult to assess and may require special tests. The development of visual acuity is a critical milestone, and any significant delay may indicate a vision problem that needs early intervention. Pediatricians and ophthalmologists often screen for visual acuity issues in children at various ages, with significant emphasis on testing around the ages of 3-5 years.

## Correct Answer: C. 5 years.