The best way to clean the chips out of a file is to use:

Using a file card to clean chips out of a file is the best option because a file card is specifically designed for this purpose. It features a bristled surface that effectively dislodges and removes metal filings and debris from the grooves of the file without damaging the file itself. This cleaning method helps maintain the effectiveness and longevity of the file, ensuring its cutting performance remains optimal.

Other methods, although they can be useful in certain situations, may not be as effective. For example, a wire brush might be too abrasive and can wear down the file's teeth, while a rag may not adequately penetrate the grooves to remove all the debris. Compressed air could move chips around but may not remove them entirely, particularly from the tighter spaces in the file's texture.

Thus, utilizing a file card is the most efficient and safe method to keep files clean and functional.