Solution: The following are the factors that cause xylem sap to rise in plants:

Mutual attraction between water molecules is referred to as cohesion.

Water molecules are drawn to the polar surface via adhesion.

Since there is active absorption by roots, root pressure is a positive pressure that pushes sap from below.

The attraction of water molecules to each other in the liquid phase is greater than the attraction of water molecules to each other in the gas phase.

Transportation Pull: As the xylem sap is drawn under negative pressure by transpiration in the aerial areas, water is continuously withdrawn.