Deficiency of which one of the following causes Xerophthalmia ?

Xerophthalmia is a progressive eye disease primarily caused by a deficiency of Vitamin A (retinol) [t1][t2]. Vitamin A is essential for vision as it is a critical component of the protein that absorbs light in the retinal receptors [t4]. A lack of this nutrient leads to the drying out of tear ducts and eyes, which can progress from night blindness (nyctalopia) and Bitot's spots to more severe conditions like corneal xerosis and keratomalacia [t3][t5]. According to the World Health Organization, Vitamin A deficiency is a major public health concern and the leading cause of preventable childhood blindness globally [t3][t6]. While other vitamins like B12 and C are vital for blood health and scurvy prevention respectively, they are not the causative factors for xerophthalmia [c1][t7].

Sources

1. [1] https://www.sciencedirect.com/topics/medicine-and-dentistry/vitamin-deficiency
2. [2] https://www.ncbi.nlm.nih.gov/books/NBK431094/
3. [3] https://www.sciencedirect.com/science/article/abs/pii/S0738081X21000742
4. [4] Science-Class VII . NCERT(Revised ed 2025) > Chapter 6: Adolescence: A Stage of Growth and Change > Science and Society > p. 80