Explanation:
Evapotranspiration refers to the process of water being transferred from the land surface to the atmosphere through the processes of evaporation and transpiration. It occurs throughout the day and night, as long as the environmental conditions are favorable. Therefore, the correct answer is option D, which states that evapotranspiration is not confined to daylight hours or land surfaces only.

Factors affecting evapotranspiration:
Evapotranspiration is influenced by various factors such as:

1. Temperature: High temperatures increase the rate of evapotranspiration.

2. Humidity: High humidity reduces the rate of evapotranspiration.

3. Wind speed: High wind speeds increase the rate of evapotranspiration.

4. Soil moisture: Drier soils increase the rate of evapotranspiration.

5. Vegetation cover: Vegetation cover affects the rate of transpiration and hence evapotranspiration.

Importance of evapotranspiration:
Evapotranspiration plays a crucial role in the water cycle and the hydrological cycle. It is responsible for the movement of water from the land surface to the atmosphere, which in turn affects weather patterns and climate. It also affects the amount of water available for plant growth and agricultural activities.

Conclusion:
Evapotranspiration is not confined to daylight hours or land surfaces only. It occurs throughout the day and night as long as the environmental conditions are favorable. It is an important process in the water cycle and affects weather patterns, climate, and plant growth.