Eco mark is given to a product which is

1. A

   Un-adulterated

   Option (a) claims the mark is given to un-adulterated goods. However, un-adulterated food products are typically certified by standards like Agmark rather than the Eco mark. Therefore, this option is incorrect.

2. B

   Economically viable

   Option (b) claims the mark signifies an economically viable product. Economic viability relates to financial feasibility and market success rather than ecological standards. Thus, this option is not the key.

3. C

   Environment friendly

   Option (c) claims the Eco mark is given to a product which is environment friendly. The Government of India instituted this label in 1991 for products conforming to specific environmental standards to reduce ecological impact. This comprehensive standard makes it the correct and longest option.

4. D

   Rich in carbohydrate

   Option (d) claims the product is rich in carbohydrate. Carbohydrate content is a nutritional metric typically denoted on food packaging rather than an environmental certification. Hence, this option is incorrect.

Summary. Official key is (c) Environment friendly. The Eco mark scheme was launched by the Ministry of Environment and Forests in 1991 to identify consumer products that cause least environmental damage. This distinguishes it from marks certifying purity, economic viability, or nutritional content. Understanding this helps candidates avoid confusing Agmark with Eco mark. Therefore, option (c) is the correct answer.