Final answer:
A. Acidic (pH 4-5)
The optimal pH range for lysosomal enzymes is acidic, around pH 4-5, which allows them to effectively degrade materials within the acidic environment of lysosomes.
Step-by-step explanation:
The optimal pH range for lysosomal enzymes to effectively degrade materials is acidic, specifically around pH 4-5. This acidic environment is crucial for the activity of these enzymes, which are designed to operate within the low pH found inside lysosomes.
Unlike enzymes that work in neutral conditions like those in the blood (pH 7.4), or ones that are adapted to more alkaline environments, such as trypsin (which works at pH 8 in the intestine), lysosomal enzymes are optimized for the acidic pH that is maintained by proton pumps in the lysosome membranes.