Final answer:
Good sources of folate include oranges and whole-grain products, as they fall into the fruit and bread/cereal food categories, respectively. Folate is essential for women who might become pregnant to prevent birth defects, hence the recommended daily intake of at least 400 µg.
Step-by-step explanation:
A good source of folate includes several types of foods. Notably, dark green vegetables, legumes, nuts, and whole grains are rich in folate.
Among the options provided, oranges and whole-grain products are good sources of folate.
Oranges are part of the fruits category, and whole-grain products belong to the bread and cereal group that are enhanced with added nutrients, including folate.
The reason the Food and Nutrition Board of the Institute of Medicine recommends that all women who might become pregnant consume at least 400 µg/day of folate is because folate is critical during the early stages of fetal development, helping prevent birth defects of the brain and spine.
Therefore, maintaining adequate levels of folate is essential for women of childbearing age.