Sustainable Development

The governing concept is the spatial dimension of sustainable development. Sustainability is not judged only by how much an economy produces or how many resources it uses; it also asks where benefits, risks, and environmental costs occur. If one region receives employment, infrastructure, and income while another bears pollution, displacement, or resource depletion, development is spatially unjust and cannot be considered fully sustainable. Option A is correct because it applies the idea of equity between places and considers both gains and costs. Option B measures output alone, option C encourages resource exploitation without safeguards, and option D focuses narrowly on urban expansion. None of those alternatives addresses regional justice or ecological balance.

The spatial dimension concerns how development benefits and environmental costs are distributed among places. A project may increase production but still burden one region with pollution or resource loss while benefits go elsewhere. Option B is correct because it addresses fairness in that regional distribution.

The governing concept is integrated river-basin planning, an important approach to sustainable development. A river basin functions as a connected system: rainfall, runoff, sediment, pollutants, groundwater interactions, ecosystems, and human uses in an upstream area can influence water quantity and quality downstream. Administrative boundaries do not stop these physical flows, so planning only within separate jurisdictions can shift problems rather than solve them. Option A correctly states the reason for treating the basin as one unit. Option B is the opposite of the basin-system idea. Option C reduces planning to river length, ignoring drainage, people, and ecology, while D incorrectly claims that political borders control natural water movement.