An enzyme is a biomolecule that increases the rate of a chemical reaction. which of the following is true about enzymes?

(I just finished Bio chemistry in my class. Ill tell you what I know about enzymes and hope itll help you, but if it doesnt, could you list the awnsers?)

-Enzymes are protiens
-Enzymes speed up the chemical process of breaking down material (like food)
-All enzymes have an 'Active sight' that attatch the substrate
-Active sight and substrate fit like a puzzle peice (can slightly alter to perfectly fit)

Ithink the answer is d.