Which one of the following cell organelles are enclosed by a single membrane?

Lysosomes are the unit membrane-bound vesicular structures formed by the process of packaging in the Golgi apparatus rich in hydrolytic enzymes like hydrolases, lipases, proteases, carbohydrases, and nucleases which are optimally active at the acidic pH. These enzymes are capable of digesting carbohydrates, proteins, lipids,, and nucleic acids.