Fotis is removing data from media. Which of the following is the least effective method?

Erasing, which describes a typical deletion process in many operating systems, typically removes only the link to the file and leaves the data that makes up the file itself. The data will remain in place but not indexed until the space is needed and it is overwritten. Degaussing works only on magnetic media, but it can be quite effective on it. Purging and clearing both describe more elaborate removal processes.