It gets polluted from fertilizers or any spilled chemicals. And those chemicals get obsorbed into the ground. And the gravity pushes them deeper in the soil, till it reaches the underground water (or aquifer)
Th correct answer is Phloem.
The conducting tissues in plants is called as the vascular tissues. It is made up of more than one type of cell type, that is found in vascular plants. The important components of vascular tissue are xylem and phloem. The function of these tissues are to transport fluid and nutrients inside the plant. Phloem is responsible for the transportation of sugar, protein and organic substances in plants. The vascular plants grow higher than other plants because of this transportation system.