Hydrolysis is an example of d) decomposition reaction.
In hydrolysis, a compound is broken down into smaller molecules by the addition of water. This process involves the splitting of chemical bonds, leading to the breakdown of a complex molecule into simpler ones. For instance, when a disaccharide like sucrose undergoes hydrolysis, it is converted into two monosaccharides, glucose and fructose, by the action of water. This is in contrast to synthesis reactions, where smaller units combine to form a larger compound, or dehydration synthesis, which involves the removal of water to join molecules together. Therefore, hydrolysis clearly fits the definition of decomposition, as it involves the breaking down of a substance rather than building it up.