Hydrolysis is best described as:

• A. A reaction in which polymer bonds are formed by removing water
• B. A reaction in which water is used to break down a polymer
• C. A reaction that requires removal of water to proceed
• D. A reaction that converts polymers into nanoparticles

Answer: (B)

Hydrolysis is a reaction where water is used to break bonds in a molecule, typically splitting a larger molecule like a polymer into smaller units or monomers. In polymers, water donates a hydrogen to one fragment and a hydroxyl group to the other, effectively inserting water across the bond and cleaving it. This description matches the statement that water is used to break down a polymer.

The other descriptions miss the core idea: forming bonds by removing water is dehydration synthesis (opposite of hydrolysis, not hydrolysis), removing water to proceed contradicts the need for water in hydrolysis, and converting polymers into nanoparticles is a different process not defined by hydrolysis alone.