A
Building transport corridors exclusively along mountain ridges and river valleys
B
Treating upper reaches (ridges) first to control runoff velocity before undertaking soil structures in the lower valleys
C
Focusing exclusively on valley agriculture while ignoring upper catchment forests
D
Constructing dams only at the river mouth near the valley floor
Correct answer: (b) Treating upper reaches (ridges) first to control runoff velocity before undertaking soil structures in the lower valleys
Explanation
Option B is correct because the ridge-to-valley approach prioritizes treating upper catchment areas (ridges) to control runoff velocity and manage water flow before implementing structures lower down in the valleys. Options A, C, and D misrepresent this core watershed conservation principle.
Same topic · past papers
UPSC has asked this before
These previous-year questions sit on the same topic. Open one to practise the earlier ask.