\\\\(\ extbf{Concept Applied:}\\\\) Knowledge of \\\\(pH\\\\) helps to determine the treatment that needs to be done on the soil.\\\\(\ extbf{Correct Option:}\\\\) A\\\\(\ extbf{Explanation for correct option:}\\\\) To improve quality and reduce the basic nature of the soil, the organic matter must be added to the soil. Organic matter releases acids that can neutralize the base of the soil and hence the quality of soil can be improved.\\\\(\ extbf{Explanation for incorrect options:}\\\\) (B) Quick lime \\\\((CaO)\\\\) is basic so it will not be helpful.(C) Slaked lime \\\\((Ca(OH)_2)\\\\) is also basic and not be helpful to reduce \\\\(pH\\\\).(D) Calamine \\\\((ZnCO_3)\\\\) is also basic and not be helpful to reduce \\\\(pH\\\\).