If there is inequality in the pattern of population growth, there is greater inequality in food production and utilisation. As societies become wealthier, their consumption of animal products increases. This means that a greater proportion of such basic foodstuff as grains and legumes that could feed humans directly is instead being converted into feed for poultry and large farm animals. Yet this conversion of plant-based food into animal food for humans is far from efficient. Only 16% of the calories fed to chickens are recovered by us when we eat them. This conversion rate goes down to five to seven per cent in large animals that are fed grain to add fat and some protein before slaughter.

Which one of the following statements best reflects the crux of the passage?

The correct option is: Animal-based food is far less efficient than grain/plant-based food in terms of production and utilisation.

Step-by-Step Explanation:

1. Understanding the Core Message of the Passage:
The passage starts by highlighting that there is great inequality in food production and utilization. It explains that in wealthier societies, the consumption of animal products rises, leading to more basic foodstuffs (like grains and legumes) being diverted to feed livestock rather than feeding humans directly.
It then explicitly states that this conversion of plant food to animal food is "far from efficient", backing it up with statistics: only 16% of calories fed to chickens and 5% to 7% of calories fed to large animals are recovered when consumed by humans.

2. Evaluating the Options:

• Option 1: Suggests an urgent need for public policy to promote cereal-based food. While this might be a potential policy implication, the passage itself does not discuss or recommend public policy measures.
• Option 2 (Correct Answer): Directly captures the central point (crux) of the passage—that converting plant-based/grain foods into animal-based foods is highly inefficient in terms of production, caloric conversion, and utilization.
• Option 3: States that plant-based protein should replace animal-based protein. The passage focuses on describing the efficiency rates of food conversion rather than giving a moral or dietary prescription on complete replacement.
• Option 4: Claims inequality is inevitable in fast-changing societies. The passage mentions inequality in food production/growth patterns, but it does not argue or conclude that such inequality is inevitable.

Conclusion:
Therefore, the statement that best reflects the crux of the passage is: Animal-based food is far less efficient than grain/plant-based food in terms of production and utilisation.