The correct answers are niacin, riboflavin, thiamin, and folic acid.
Whole grains (for example oatmeal and brown rice) have the whole grain kernel, including the endosperm, germ, and bran. After going through the refining process, which lengthens shelf life and creates a finer texture, it is left with only the endosperm. These refined grains (like white bread and white rice) thus lose B vitamins as well as iron and fiber.