Correct option is A
The proponents of a plant-based diet emphasize the following:
- (A) Animal-based diets result in greater thermodynamic energy loss because energy is lost at each trophic level (from plants to herbivores to carnivores). More energy is required to produce animal-based foods, making plant-based diets more energy-efficient.
- (B) The production of animal-based foods results in high carbon emissions, often due to the need for extensive land use, animal feed production, and energy consumption. Animal farming releases more CO₂ and methane compared to plant-based farming.
These two statements highlight the inefficiency and environmental cost of animal-based diets, which is why A and B form the core of the sustainable development argument for a plant-based diet.
Explanation of Other Options:
- (C) While animal tissues have high C:N ratios, this is not as directly linked to sustainability as energy loss and carbon emissions.
- (D) While animal tissues have high water content, this does not directly argue for sustainability since both plant and animal products require water, but animal products generally need more water to produce due to the inefficiencies of animal farming.
Information Booster:
- Thermodynamic energy loss: Every step in the food chain leads to energy loss (10% rule), and animal-based diets contribute to greater energy inefficiencies.
- Carbon burn-off: Animal farming is carbon-intensive, with significant emissions from land use and animal digestion (e.g., methane).
- C:N ratio: Animal tissues have higher carbon relative to nitrogen than plants, but this does not contribute as directly to the argument for reducing environmental impact.
- Water usage: While animal farming does consume more water, the greater concern is energy and carbon footprints.
