Why Does Vitamin a Status Depend on the Person's Protein

Why does vitamin A status depend on the person's protein status?

A) Adequate protein intake is a marker for liberal intake of the vitamin
B) Dietary protein ensures synthesis of the vitamin's GI tract transporter
C) Adequate protein intake reduces the risk for infection from bacteria that degrade the vitamin
D) Transport of the vitamin within the body requires sufficient protein to synthesize retinol-binding protein