Answer:
The correct answer would be the first option.
Enzymes are bio-catalyst which increase the rate of biochemical reaction taking place in our body.
They reduce the activation energy of the reaction by forming the enzyme-substrate complex.
A specific substrate binds to the active site of a specific enzyme in order to form an enzyme-substrate complex.
It is then converted into enzyme-product complex after which product is released and the enzyme is ready for another round of reaction.
Enzyme + Substrate → Enzyme-Substrate complex → Enzyme-Product complex → Enzyme + Product.