Final answer:
The distribution of Vitamin A supplements has contributed to a reduction in childhood mortality in developing countries.
Step-by-step explanation:
The distribution of Vitamin A supplements has contributed to a nearly 23% reduction in childhood mortality in numerous developing countries. Vitamin A deficiency is common in these countries, and it adversely affects the immune system, increases the risk of infections, contributes to anemia, and can cause visual impairments. By distributing Vitamin A supplements, these countries are addressing this deficiency and improving the health outcomes for children.