How does the lysosome maintain an acidic environment, which is crucial for its digestive function?

• A. By importing acidic molecules from the cytoplasm.
• B. By producing acid as a byproduct of digestion.
• C. By pumping protons (H⁺ ions) into the lysosome via ATP-dependent proton pumps.
• D. By relying on the acidic environment of the cytoplasm.

Answer: (C)