The correct answer is option 2: environment-friendly.
The Eco-Mark is a certification mark awarded by the Bureau of Indian Standards (BIS) to products that meet specific environmental standards. This mark is given to Indian products that are considered to be environmentally friendly in their manufacturing, usage, and disposal.
Option 1, "rich in protein," is not a requirement for the Eco-Mark. While some products may have nutritional benefits, the focus of the Eco-Mark is on their environmental impact.
Option 3, "economically viable," is also not the main criteria for the Eco-Mark. The mark emphasizes the environmental sustainability of the product rather than its economic viability.
Option 4, "pure and unadulterated," is unrelated to the Eco-Mark. This option refers to the quality and purity of a product, which is a separate consideration from its environmental impact.
In conclusion, the Eco-Mark is given to Indian products that are considered to be environment-friendly, as they meet specific environmental standards set by the BIS. None of the other options are directly related to the criteria for receiving the Eco-Mark.