Assertion: In India irrigation facilities are also required even in the areas of ample rainfall like West Bengal and Bihar.

Reasoning: In the absence of irrigation facilities, breaks in monsoon or its failure creates dry spells which will be detrimental for agriculture.

Both Assertion (A) and reasoning (R) are correct and R is the correct explanation of A.

The correct answer is Option 1: Both Assertion (A) and reasoning (R) are correct and R is the correct explanation of A.

Assertion: In India irrigation facilities are also required even in the areas of ample rainfall like West Bengal and Bihar.This is correct. This is correct because agriculture depends not only on the total amount of rainfall but also on its regularity and timely distribution.

Reasoning: In the absence of irrigation facilities, breaks in monsoon or its failure creates dry spells which will be detrimental for agriculture. This is also correct.  The monsoon frequently experiences "breaks" (periods of no rainfall) or delays. Relying solely on rainfall can lead to moisture stress during critical growth stages of crops. Irrigation acts as a vital buffer, ensuring water availability during these dry spells and protecting crops from failure. 

Does R explains A? Yes. The Reason correctly explains the Assertion because even though states like West Bengal and Bihar receive high annual rainfall, the rainfall is seasonal and uncertain. During breaks in the monsoon, crops may not get water at critical stages of growth. Irrigation acts as a protective measure by ensuring a continuous water supply and preventing crop failure during such dry spells.

NCERT: " In agriculture, water is mainly used for irrigation. Irrigation is needed because of Spatio-temporal variability in rainfall in the country. The large tracts of the country are deficient in rainfall and are drought-prone. North-western India and Deccan plateau constitute such areas. Winter and summer seasons are more or less dry in most part of the country. Hence, practicing agriculture without assured irrigation during dry seasons is difficult. Even in the areas of ample rainfall like West Bengal and Bihar, breaks in monsoon or its failure creates dry spells detrimental for agriculture. The water need of certain crops also makes irrigation necessary. For instance, rice, sugarcane, jute, etc. water requirement is very high and can be met only through irrigation."