(A), (B) and (C) are correct.
First of all, in real-world terms, privacy invasion is a threat to privacy, not security. Privacy and security are two different things. In fact, it is possible to provide more national security with more privacy invasion.
privacy invasion, in the form of access of personal data, is a threat to data security.
Power failure, resulting in data in volatile memory not being saved to permanent memory. Hardware failure, such as a head crash in a hard disk. A software crash or freeze, resulting in data not being saved.
Data or disk file encryption and decryption is an important means of data protection, so by way of stealing passwords or illegal access to confidential data and information on the computer is a data security threat.
