What is the primary characteristic of myopia?

Myopia, commonly known as nearsightedness, is a refractive error of the eye where distant objects appear blurry while close objects can be seen clearly. This condition occurs when the eyeball is too long relative to the focusing power of the cornea and lens, causing light rays to focus in front of the retina instead of directly on it. The result is that a person with myopia will struggle to see things clearly at a distance, hence the term "nearsightedness."

The other options—farsightedness, astigmatism, and color blindness—describe different visual conditions. Farsightedness involves difficulty seeing close objects clearly, which is the opposite of myopia. Astigmatism is a condition characterized by an irregular curvature of the cornea or lens, leading to blurred or distorted vision at all distances. Color blindness is a deficiency in perceiving certain colors, unrelated to the clarity of vision for distances. Therefore, myopia is specifically detailed by its primary characteristic of near-sightedness.