Achemical reaction is the process by which a takes place

A chemical reaction is the process by which a change takes place

Explanation:

A chemical reaction is a process by which one or more substances, called reactants, are transformed into one or more other substances with different properties, called products.

The bonds between the atoms that make up the reactants are broken. Then, the atoms rearrange themselves in another way, forming new bonds and giving rise to one or more different substances from the initial ones. So the atoms do not change, they remain the same, but it changes is the way they are linked together.

In short, chemical reactions are the process of arranging atoms and bonds when chemicals come into contact. The chemical properties change by altering the arrangement of the atoms in that substance.

So, a chemical reaction is the process by which a change takes place.

a is the correct answer