What is the benefit of irrigation with river water?

Correct answer: It helps crop production

Irrigation is the planned supply of water to agricultural land when rainfall is insufficient, irregular, or unavailable at the required time. Crops need water for processes such as germination, growth, and formation of flowers or grains. River water, when properly managed and suitable for use, can be carried through canals, channels, pumps, or other systems to fields. This helps farmers maintain crop growth and may support cultivation beyond the rainy season. Irrigation does not guarantee success by itself, but it directly supports agricultural production.

Option A is correct because supplying river water to fields helps crops receive the moisture they need. The other choices contradict the purpose of irrigation. Water does not necessarily disappear, fields do not always become barren, and irrigation cannot close the source of a river. The benefit described is general and does not claim that every irrigation system is perfect or risk-free. It simply identifies the direct agricultural advantage: a more dependable water supply can assist crop production.