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Natural Resources — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceNatural Resources1 Mark
MCQ
Eutrophication results in reduction of:
  • A
    Dissolved hydrogen.
  • ✓
    Dissolved oxygen.
  • C
    Mineral salts.
  • D
    Dissolved nitrate.
✓

Answer

Correct option: B.
Dissolved oxygen.
Eutrophication leads to algal blooms in water bodies thus blocking the penetration of sunlight in the water bodies. Hence the plants do not get sufficient sunlight to carry out photosynthesis hence oxygen is not produced.

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