Answer: Water molecules connect through hydrogen bonds.
This is because of hydrogen bond the molecules of water stick to each other and this phenomenon is known as cohesion.The roots of the plants acts as capillary. Due to the cohesion property of water all the water present in the soil seems to be a single molecule of large size. The property of water to stick to another substance is known as adhesion. Due to this property the water sticks to the roots of the plant. The property of cohesion along with adhesion is responsible to draw water up from roots.