Choose the statement that best describes sustainable development.

1. Sustainable development is development that focuses on the resources available to meet the needs of the world's population.
2. Sustainable development is development that focuses on the resources that the environment can provide to meet future needs.
3. Sustainable development is development that is designed to improve the economic conditions of populations in the world's less developed countries (LDCs).
4. Sustainable development is development that meets the world's current needs while making sure that resources will be available to meet future needs.