Which of the following undergoes reduction with `H_(2)O_(2)` in an alkaline medium ?

H_(2)O_(2) exists in alkaline medium as

Which one of the following compounds on reaction with Na_(2)O_(2) in alkaline medium gives yellow colour solution?

Which one of the following compounds on reaction with Na_(2)O_(3) in alkaline medium gives yellow colour solution?

Which one of the following compounds on reaction with Na_(2)O_(3) in alkaline medium gives yellow colour solution?

Which of the following undergoes reduction with hydrogen peroxide in an alkaline medium ?