Answer:
D. Leak-proof
Explanation:
Used oils are required to be stored in closed containers or tanks which will remain closed when oil is not added or removed. Alternatively, used oils can be stored in containers labeled "Used Oil" for regulated hazardous waste storing. A leak-proof container is one that has no drips and dribbles when the container lid is closed. These containers should be kept in good conditions away from rusting, leaks or deteriorations. It is important to mention that used oil should not be stored in anything apart from tanks and leak-proof storage containers.
