Which vitamin deficiency is characterized by night blindness?

Night blindness, or impaired vision in low light or darkness, is primarily associated with a deficiency in vitamin A. This vitamin is crucial for the production of rhodopsin, a pigment found in the retina that is essential for night vision. Without adequate levels of vitamin A, the eyes cannot adjust properly to the dark, leading to difficulty seeing in low-light conditions.

Vitamin A also plays several other roles in maintaining overall eye health and integrity of the visual system. It is necessary for the health of the cornea and the conjunctival membranes, contributing to good vision and eye health. Therefore, when vitamin A levels are insufficient, it directly affects the function of the eyes, resulting in symptoms such as night blindness.

Other vitamins listed do have their own important functions in the body, but they do not directly relate to the symptom of night blindness.