Answer: A - Uptake of food and water by plants
The xylem vessels in the roots of the plants use the mechanism of capillary action and work against gravity to pull water molecules and nutrients from the soil and carry them upwards to the leaves of the plant to provide nourishment to the plant.
A water molecule (H2O) will have a slightly positive side, and a slightly negative side. The oxygen side of water is the one that is negative, while hydrogen side tends to be more positive. When a molecule has a half negative and half positive side like water does, it is called a polar molecule. :D
The answer to this question might be protein.
