Environmental Science

Step 1: Understand the core concept described.
The question describes a process of development that not only meets present needs but also ensures that future generations can meet their own needs, thereby sustaining human well-being into the future.

Step 2: Define the terms in the options.
- (1) Eco-System: A biological community of interacting organisms and their physical environment.
It's a unit of nature, not a process of development.
- (2) Bio-Diversity: The variety of life in the world or in a particular habitat or ecosystem.
It is something to be conserved for sustainable development.
- (3) Sustainable Development: Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
It integrates economic, social, and environmental considerations.
This directly matches the description in the question.
- (4) Natural Resources: Materials or substances such as minerals, forests, water, and fertile land that occur in nature and can be used for economic gain.
Sustainable development involves the wise use of natural resources.

Step 3: Identify the term that fits the definition.
The process of development that sustains human well-being for the present and future generations is known as Sustainable Development.
This matches option (3).