Verbal Aptitude

Paradox: 'A soil conservation project installed thousands of rock check dams across gullies in an upper catchment. Downstream reservoir siltation rates did not decrease over the subsequent three years.' Which finding best resolves the paradox?

Options:

• (A) The initial construction activities and heavy vehicle movements destabilized adjacent steep gully banks, generating loose sediment that offset the trapping capacity of the dams.
• (B) Check dams are built from porous rock.
• (C) Sedimentation reduces reservoir storage capacity.
• (D) Check dams slow down stream water velocity.