Question

to decrease as shown in the graph? lipid protein carboydrate nucleic acid

Explanation:

Enzymes are biological catalysts, and most enzymes are proteins. The graph shows the effect of an enzyme (which is a protein) on reducing activation energy. Lipids, carbohydrates, and nucleic acids do not function as enzymes (catalysts that lower activation energy in this context). So the molecule that causes activation energy to decrease (the enzyme) is a protein.

Answer:

protein