What is the function of vitamin A?

Vitamin A, also known as retinol, has several important functions. These include: helping your body's natural defence against illness and infection (the immune system) work properly. helping vision in dim light.

Explanation:

Vitamin A helps form and/or maintain bones, soft tissue, mucus membranes, healthy teeth and skin.

pathogens is the answer

a problem could be dealing witj emotional stress..all of these factors contribute to emotional stress.