Answer:
A. ENZYMES
Explanation:
Enzymes are the catalysts of reactions found in living things. Enzymes can be best described as kind of proteins that serve as biological catalysts. They majorly function in increasing the speed of biological reactions by lowering the activation energy . Enzymes do not effect the equilibrium of any reaction. Also, enzymes itself are not used up in any reaction, however transient changes can occur in them due to the reaction. Enzymes are specific for different substrates.
