Given below are two statements. In the light of the above statements, choose the correct answer from the options given below.
Statement I:The amount of oxygen dissolved in water is a good indicator of water quality and of the kinds of life it will support.
Statement II:Chemical Oxygen Demand (COD) is a measure of the dissolved oxygen consumed by aquatic microorganisms.
ABoth Statement I and Statement II are true
BBoth Statement I and Statement II are false
CStatement I is true but Statement II is false ✓ Correct
DStatement I is false but Statement II is true
Correct answer: (C) Statement I is true but Statement II is false
Explanation
Statement 1 is correct, as dissolved oxygen is a good indicator of water quality and the life a water body supports.
Higher dissolved oxygen generally means healthier aquatic ecosystems.
Statement 2 is wrong, because oxygen consumed by aquatic microorganisms is measured by biochemical oxygen demand, not COD.
Chemical oxygen demand measures the oxygen equivalent of chemical oxidation of organic and inorganic matter.
The two statements differ, one describing DO accurately and the other misdefining COD.
High BOD or COD signals heavy organic pollution and low water quality.
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