American Association of Family and Consumer Sciences (AAFCS) Practice Test 2025 - Free AAFCS Practice Questions and Study Guide

The primary function of vitamin A in the human body is to support vision, particularly in low-light conditions, and plays a crucial role in maintaining healthy skin and mucous membranes. While vitamin A does have an indirect impact on overall health, particularly through its contributions to immune function and reproduction, the other functions listed in the choices are not the primary roles of vitamin A.

Vitamin A is essential for the synthesis of rhodopsin, a pigment in the retina that is crucial for the proper functioning of night vision. Additionally, it supports the growth and differentiation of epithelial cells, which are vital for maintaining the health of both the skin and various bodily tissues. It does not directly aid in bone growth, strengthen hair and nails, enhance muscle function, or promote cognitive function in the way that other nutrients might. The confusion may arise from the broad health benefits associated with vitamin A, but its most well-known and critical function is in vision.