**Core Concept**
Visual acuity is a measure of the sharpness of vision, typically expressed as a fraction where the numerator is the distance at which a person can read a standard Snellen chart and the denominator is the distance at which an individual with normal vision can read the same line. The Snellen chart is used to assess visual acuity, with higher numbers indicating poorer vision.

**Why the Correct Answer is Right**
The Snellen chart is designed so that a person with normal vision (20/20) can read the largest line at a distance of 20 feet. Since the person in this question has a visual acuity of 6/6, they can read the largest line at 6 meters. To determine the distance at which they can read 6/24 lines, we can use the ratio of the visual acuities and the distance at which they can read the largest line. Since 6/6 is equivalent to 20/20, and 6/24 is equivalent to 20/80, we can set up a proportion to find the distance. (6/24) / (6/6) = (x / 6), where x is the distance at which they can read 6/24 lines.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided, so it cannot be evaluated.
**Option B:** This option is not provided, so it cannot be evaluated.
**Option C:** This option is not provided, so it cannot be evaluated.
**Option D:** This option is not provided, so it cannot be evaluated.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the Snellen chart is used to assess visual acuity, and the ratio of the visual acuities can be used to determine the distance at which a person can read a specific line. This can be a useful tool in clinical practice when assessing a patient's vision.

**Correct Answer: B. 96 meters**