Final answer:
The most likely pH to favor the operation of a lysosomal enzyme is 4.5, which is more acidic and closer to the pH range found within lysosomes.
Step-by-step explanation:
The lysosomal enzymes have an optimum pH at which they work most effectively. Since lysosomes are organelles responsible for breaking down waste materials and cellular debris, they require an acidic environment with a low pH. The pH that would be most likely to favor the operation of a lysosomal enzyme is 4.5, as this pH is more acidic and closer to the pH range found within lysosomes.