Which reaction helps us to break down a disaccharides into two same or different monosaccharides units?

Hydrolysis

The answer is (2) Hydrolysis.

Hydrolysis is a chemical reaction that breaks down a compound into two or more simpler compounds by adding water. In the case of disaccharides, hydrolysis breaks the glycosidic bond between the two monosaccharide units, releasing the two monosaccharides.

Hydration is the opposite of hydrolysis, which involves adding water to a compound. Oxidation is the loss of electrons, and reduction is the gain of electrons. So, neither hydration, oxidation, nor reduction can break down a disaccharide into two monosaccharide units.