Enzymes are reusable biological catalysts

Steps:

• Define enzymes as proteins or RNA that speed up reactions without being consumed.
• Check A: Enzymes are typically proteins, aligning with standard biology.
• Check B: Matches the catalyst role in lowering activation energy.
• Check C: Contradicts the reusable nature of enzymes.
• Check D: Aligns with human body temperature optimum near 37°C.

Why C is correct:

• Enzymes act as catalysts and remain unchanged after reactions, per the definition of catalysis where they are regenerated.

Why the others are wrong:

• A: Most enzymes are proteins, a core biochemical fact.
• B: Enzymes function as biological catalysts by definition.
• D: Optimal temperature for human enzymes reflects physiological conditions around 37°C.

Final answer: C