## Core Concept
The axial length of the eye is a critical measurement in ophthalmology, referring to the distance from the anterior surface of the cornea to the retina along the visual axis. It is an essential parameter in the calculation of intraocular lens power for cataract surgery and in the assessment of various ocular conditions. The normal axial length typically ranges within specific limits.

## Why the Correct Answer is Right
The correct axial length of the eye is approximately **22-24 mm** in adults. This range allows for proper focusing of light onto the retina. The axial length can vary slightly among individuals, but significant deviations from this range may indicate ocular abnormalities such as myopia (nearsightedness) for longer lengths or hyperopia (farsightedness) for shorter lengths.

## Why Each Wrong Option is Incorrect
- **Option A:** This option is incorrect because it does not fall within the normal range of axial length.
- **Option B:** This option is incorrect as it is either too short or too long compared to the established normal range.
- **Option D:** This option is incorrect because it also does not align with the accepted normal axial length of the human eye.

## Clinical Pearl / High-Yield Fact
A key clinical point to remember is that axial length measurements are crucial in the diagnosis and management of refractive errors and in planning for cataract surgery. Abnormal axial lengths can lead to vision problems, and accurate measurements are essential for corrective procedures.

## Correct Answer Line
**Correct Answer: C. 22-24 mm.**