Which of the following factors contributes to capillarity in xylem vessels?Repulsion between water and xylem cell wallsAdhesive force between water and xylem cell wallsAttraction between water and airTranspiration pull

The factor that contributes to capillarity in xylem vessels is the adhesive force between water and xylem cell walls.

Here's a step-by-step explanation:

1. Capillarity refers to the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity.

2. This phenomenon occurs due to the intermolecular forces between the liquid (in this case, water) and the surrounding solid surfaces (in this case, the xylem cell walls).

3. The adhesive force between water and xylem cell walls allows water to "stick" to the sides of the vessels. This is due to the polarity of water molecules, which are attracted to the polar surfaces of the xylem vessels.

4. As a result, water can move upwards against gravity in the xylem vessels, a process that is crucial for the transportation of water from the roots to the rest of the plant.

5. Therefore, the adhesive force between water and xylem cell walls is the factor that contributes to capillarity in xylem vessels.

The other options listed do not contribute to capillarity. Repulsion between water and xylem cell walls would hinder capillarity, not promote it. Attraction between water and air does not directly contribute to capillarity in xylem vessels. Transpiration pull does contribute to the overall movement of water in xylem, but it is not a factor in capillarity.