According to the current (2005) Dietary Guidelines for Americans:
A. people over the age of 50 better absorb vitamin B12 in comparison to children and other adults
B. non-heme (plant) sources of iron are richer than heme (animal) sources of iron for women of childbearing age
C. women of child-bearing age who may become pregnant require a higher daily intake of folic acid than the pregnant female
D. the elderly and individuals with dark skin are at greater risk of low vitamin D concentrations than other populations
Answer: D