The Movement of Water Through Plants Is

The movement of water through plants is

A) maintained during the day by the positive water potential of the air.
B) along a gradient where the water potential is lower in the roots and higher in the leaves.
C) possible because xylem sap is more dilute than root cell vacuoles.
D) along a water potential gradient maintained in the xylem by negative hydrostatic pressure.
E) by active transport in the phloem.