Answer : The correct option is, (B) bleach
Explanation :
From the given pH chart, we conclude that the pH of the red cabbage juice is 2 that means it is acidic in nature. The red cabbage juice will turn green by the bleach because bleach is the substance which is basic in nature while the other options, milk, vinegar and stomach acid are acidic in nature.
The chemical formula of the bleach is (NaClO) sodium hypochlorite which is strongly basic in nature.
Hence, the correct option is, (B) bleach
