Answer:
A: catalyst
Step-by-step explanation:
In Chemistry, the rate of reaction of chemical elements (reactants) can be sped to produce a chemical compound or elements (products), through the addition of a catalyst that is unaffected by the reaction.
This ultimately implies that, to speed up a chemical reaction, add a catalyst that is unaffected by a reaction.
For example, an enzyme refers to a biological catalyst that is typically used to speed up (accelerate) the rate of a chemical reaction by lowering the activation energy of its reactants.
An enzyme can be defined as a biological catalyst that typically lowers the activation energy of a biological reaction. When the activation energy of a reaction is low, the rate of the reaction would be faster. Therefore, an enzyme speeds or catalyzes the rate of a reaction by lowering its activation energy.
Generally, an increase in temperature increases or speeds up the rate of a reaction while low temperature limits or reduces the rate of a reaction. The optimal temperature for enzymes in the human body is around 37 degrees celsius.