正解:A
The correct answer is A. Overwriting multiple times. Overwriting is a method of securely erasing data from a hard disk by replacing the existing data with random or meaningless data, making it difficult or impossible to recover the original data1. Overwriting multiple times, also known as multiple-pass overwriting, is a more effective way of disposing of sensitive data than overwriting once, as it reduces the possibility of residual traces of data that could be recovered by advanced techniques2. Overwriting multiple times can be done by using specialized software tools that follow certain standards or algorithms, such as the US Department of Defense's DoD 5220.22-M or the Gutmann method3.