**Core Concept**
The visual axis refers to the line connecting the point of fixation on the object being viewed to the center of the pupil in the eye. This concept is crucial in ophthalmology, particularly in understanding the anatomy of the eye and its relationship with visual perception.

**Why the Correct Answer is Right**
The correct answer is the line that represents the path of light from the object being viewed to the retina. The visual axis is essential for clear vision, as any obstruction or displacement of this axis can lead to visual disturbances. The visual axis passes through the pupil and the center of the lens, allowing light to focus on the retina. In cases of strabismus or other eye alignment disorders, the visual axis can be affected, leading to double vision or other visual symptoms.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately represent the visual axis. The visual axis is not a fixed point, but rather a line that connects the point of fixation to the pupil.
**Option B:** This option is incorrect because it refers to the optical axis, which is the line that passes through the center of the lens and the center of the retina. While related to the visual axis, the optical axis is not the same thing.

**Clinical Pearl / High-Yield Fact**
The visual axis is essential for clear vision, and any obstruction or displacement of this axis can lead to visual disturbances. This concept is crucial in diagnosing and managing eye alignment disorders, such as strabismus.

**Correct Answer:** C. The line connecting the point of fixation on the object being viewed to the center of the pupil in the eye.