When We Obtain Calcium from a Dietary Supplement,the Absorption of Magnesium

When we obtain calcium from a dietary supplement,the absorption of magnesium and copper from food may be reduced because

A) calcium interferes with the digestion of trace minerals.
B) magnesium and copper both have the same valence as the calcium,so there is competition for absorption sites.
C) excess calcium can destroy the villi of the intestinal tract.
D) excess calcium means the magnesium and copper cannot be solubilized in water.