Which option allows you to reuse graphic elements without inflating the file size?

Using symbols is an effective method for reusing graphic elements in Adobe Illustrator without significantly increasing the file size. When a graphic element is converted into a symbol, Illustrator stores it in the Symbols panel. This means that multiple instances of the symbol can be created throughout the document without duplicating the actual data. Instead of each instance containing its own separate data, they all reference the same symbol definition. This not only keeps the file size efficient but also allows for easier editing; modifying the original symbol updates all instances automatically.

In contrast, grouping elements or using layers does not offer the same benefits in terms of file size reduction. Groups organize items together but don't reduce data redundancy. Layers help with organization in the workspace but do not manage the file size concerning reused graphics. Artboards provide separate spaces for different designs but likewise don’t address the issue of reusing elements in a way that manages file size efficiently. Overall, using symbols is specifically designed to enhance efficiency and streamline the design process within Adobe Illustrator.