If you have a book, read it!! I promise you, it tells you this answer!
I believe the correct answer from the choices listed above is option D. Catalysts lower the activation energy of a chemical reaction. It <span>is a substance which speeds up a reaction, but is chemically unchanged at the end of the reaction. It provides another pathway for the reaction to occur.</span>
Neither of them are used in magnets they don’t attract metal
So, what's your question..?. You just gave options..
