What is the function of a seam ripper?

The function of a seam ripper is specifically designed for removing stitches without damaging the fabric. This tool features a pointed end that can easily slide under stitches, allowing the user to cut them while keeping the surrounding fabric intact. This capability is crucial for correcting mistakes in sewing, such as undoing seams or adjusting garment fit, without causing additional wear or damage to the fabric itself.

In contrast, the other options describe tools or functions that do not align with the purpose of a seam ripper. Sewing pieces of fabric together involves using a needle and thread, trimming excess fabric is typically done with scissors, and creating decorative stitches requires a sewing machine or specialized tools. Thus, the ability to safely and efficiently remove stitches uniquely characterizes the seam ripper.