Verified Answer :

a. enzymes without any doubt is the correct answer :)

Reusable complex protein that
promotes chemical reactions within cells are called enzymes.

 

Enzymes are biological molecules (proteins) that act as
catalysts and help complex reactions occur everywhere in life. Let's say you
ate a piece of meat. Proteases would go to work and help break down the peptide
bonds between the amino acids.

 

The correct answer between all
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