The statement mentioned above is partially true. Transpiration pull is the major factor, which facilitates movement of water in xylem. But there are other factors that also play a major role. Cohesion-adhesion and surface tension gives high capillarity to water molecules, which enables it to reach a certain height in plant’s xylem. Transpiration pull has an augmentative effect on the surface tension push. So in totality it is cohesion-adhesion-surface tension and transpiration pull, which does the whole function of transporting water to greater heights in plants.