Scientists have termed one of the following as 'green gold' based on its economic and ecological importance:

Correct answer: (c) Bamboo

Explanation

Bamboo is called green gold because of its great economic and ecological value:

• it is one of the fastest-growing plants, and it is used for building, furniture, paper, handicrafts, food (bamboo shoots) and fuel;
• its roots bind the soil and check erosion, and it absorbs much carbon.

Botanically, bamboo is a grass (family Poaceae), not a tree. India has one of the world's richest bamboo resources, and the National Bamboo Mission promotes its use.