Which of the following is not an advantage of drip-irrigation?

The option that is not an advantage of drip-irrigation is "its efficiency on water distribution in steep slopes is poor." Drip-irrigation is a method of applying water directly to the root zone of plants in a slow and precise manner. It has several advantages, such as the ability to apply fertilizers through the system, reducing the concentration of salt in the root zone, operating on a much lower line pressure than sprinkler systems, and considerable maximization of water use. However, on steep slopes, the efficiency of water distribution through drip-irrigation may be reduced because the water may flow downward too quickly, leaving some plants without adequate moisture. In such cases, other irrigation methods such as terracing or contour farming may be more suitable.