Which of the following materials can be recycled indefinitely without losing their properties or quality?

Aluminum is a material that can be recycled multiple times without losing its properties or quality. This is because it does not degrade during the recycling process, and it can be melted down and reshaped repeatedly. In contrast, plastics and organic materials can only be recycled a limited number of times before they degrade and lose their quality. Wood, on the other hand, can be recycled but not indefinitely, as it also degrades over time.