Frank uses a powerful magnet to wipe tapes before they are removed from his organization's inventory. What type of secure data destruction technique has he used?

Frank has used a degausser to erase the data on the tapes. Degaussing is a method of erasing magnetic media such as tapes, and is not applicable to optical or flash media. Burning media or materials involves placing them in a fire. Shredding and pulping, on the other hand, are mechanical methods of destruction.