Brownfield site is defined as?

• A. Green fields for farming
• B. Natural reserves
• C. Vacant industrial land never used
• D. Areas of land which were once used for urban development

Answer: (D)

Brownfield sites are land that has been previously developed for urban use—such as former factories, warehouses, or housing—that is now vacant or underused. These sites often lie in built-up areas with existing infrastructure, making them good targets for redevelopment. This contrasts with greenfield sites, which have not been developed before (for example, green fields or natural reserves). Therefore, areas that were once used for urban development fit the brownfield definition.