What is the typical file extension associated with high-quality image compression?

The file extension commonly associated with high-quality image compression is JPEG. JPEG, which stands for Joint Photographic Experts Group, utilizes a lossy compression algorithm that significantly reduces the file size of images by discarding some data, particularly in areas that are less likely to be noticed by the human eye. This compression method allows for smaller file sizes while still providing an acceptable level of image quality, making JPEG a popular choice for digital photography, web graphics, and the like.

The other options pertain to different file types. DOCX is a file format for Microsoft Word documents, TXT is a plain text file format, and XLSX is used for Microsoft Excel spreadsheets. None of these formats are related to image compression, which is specifically what the question addresses. So, the association of JPEG with high-quality image compression makes it the correct choice in this context.