What type of lens is used primarily for nearsightedness correction?

Nearsightedness, also known as myopia, occurs when light entering the eye is focused in front of the retina, typically due to a longer-than-average eyeball or excessive curvature of the cornea. To counteract this condition, minus lenses are used.

Minus lenses are concave lenses that are thinner at the center and thicker at the edges. This design allows the light rays entering the eye to diverge, pushing the focal point back onto the retina, thereby allowing for clear distance vision.

Nearsighted individuals require a negative diopter prescription, which is represented by the use of minus lenses. This corrects the vision by altering the way light is focused into the eye. Therefore, for someone with myopia, minus lenses are the primary corrective tool, making this the correct choice in the context of the question.