Which tool in Adobe Illustrator is used to create freeform shapes?

The Pencil Tool is specifically designed for creating freeform shapes in Adobe Illustrator. This tool allows you to draw shapes and lines with a natural, hand-drawn look, giving you the freedom to sketch shapes that can be as intricate or as simple as desired. When using the Pencil Tool, you can create smooth, curved lines and organic shapes without having to adhere to the straight edges or specific parameters set by other tools. It’s particularly useful for artists and designers who want to capture a more fluid and less structured style in their illustrations, making it ideal for drawing paths that don't necessarily follow standard geometry.

The other tools mentioned are more suited for creating specific geometric shapes or paths, which would limit the ability to create the freeform styles that the Pencil Tool excels at. The Polygon Tool constructs regular polygons, while the Rectangle Tool is tailored for creating rectangular shapes. The Pen Tool, while versatile and powerful for drawing, requires more precision and control, making it less suitable for freeform drawing compared to the intuitive nature of the Pencil Tool.