Which of the following statement is incorrect?

Match List - I with List - II, match the gas evolved during each reaction.

Choose the correct answer from the options given below :

Which of the following has least tendency to liberate $$\mathrm{H}_{2}$$ from mineral acids?

Given below are two statements:

Statement I : In polluted water values of both dissolved oxygen and $$\mathrm{BOD}$$ are very low.

Statement II : Eutrophication results in decrease in the amount of dissolved oxygen.

In the light of the above statements, choose the most appropriate answer from the options given below :