How does the rate of a biochemical reaction catalyzed by an enzyme change when the concentration of a non-competitive inhibitor is increased, keeping the substrate concentration constant?

The rate of reaction increases because more enzyme-substrate complexes are formed.

The rate of reaction decreases because more enzyme-inhibitor complexes are formed.

The rate of reaction remains unchanged as non-competitive inhibitors do not affect it.

The rate of reaction initially increases and then decreases.