Which nutritional deficiency could contribute to the development of intellectual disabilities?

The development of intellectual disabilities can be significantly influenced by a lack of essential vitamins and minerals. Nutritional deficiencies, especially during critical periods of brain development, can lead to impaired cognitive functioning and developmental delays. Key nutrients such as folic acid, iodine, iron, and other micronutrients play vital roles in brain health and function. For instance, folic acid is crucial during pregnancy for fetal brain development, and its deficiency has been linked to neural tube defects and cognitive impairments.

In contrast, excess vitamin C, high protein diets, and processed sugars do not have a direct correlation with the development of intellectual disabilities in the same way that a deficiency of essential nutrients does. Excessive vitamin C, for example, is generally not associated with cognitive issues, while high-protein diets can support overall health if balanced. Processed sugars, while they can impact overall health and contribute to other health issues, are not primarily linked to deficiencies that would result in intellectual disabilities. Therefore, the lack of essential vitamins and minerals is the correct answer, as it directly addresses the crucial role of proper nutrition in cognitive development.