Explanation

Phloem is the vascular tissue responsible for translocation of food — mainly sucrose and other organic solutes — from sources (leaves) to sinks (roots, fruits, growing parts), per the pressure-flow hypothesis. Water (option A) and dissolved minerals (option C) are transported upward by the xylem, not the phloem; oxygen (option B) diffuses or is transported via air spaces/blood in animals. Hence option D.