Which one of the following statements best reflects the crux of the…

People should be persuaded to continue with the mainly Indian traditional cereal-based diets.
India needs to focus on developing agricultural productivity and capacity for more energy generation in the coming years.
Modern technological developments result in the change of cultural and social behaviour of the people.
Water management practices in India need to change dramatically in the coming years.

Answer

Water management practices in India need to change dramatically in the coming years.

(a) Too narrow. This is a prescriptive dietary suggestion, not the central idea unless the passage specifically argued for preserving cereal diets as the main solution. Verdict: Not the crux.
(b) Partial at best. Agricultural productivity and energy capacity may be discussed, but this combines two broad development goals rather than the passage’s core message. Verdict: Not the best reflection.
(c) Over-generalized. Technological change affecting culture/social behaviour is a generic statement and does not capture a likely specific policy concern. Verdict: Incorrect.
(d) Most likely the crux. Such passages typically link food habits, agriculture, energy and sustainability to the central stress on water scarcity and the need for major changes in water-use/management practices in India. Verdict: Correct.