Final answer:
Stealing someone else's personal data is a case of identity theft.
Step-by-step explanation:
Out of the given options, stealing someone else’s personal data is a case of identity theft. Identity theft occurs when someone wrongfully acquires and uses another person's personal information without their permission to steal their identity. This illegally acquired information is then used for fraudulent activities, such as draining savings accounts or making unauthorized purchases.
The answer that you should select is ciphertext. The decryption key or algorithm is required to decipher this encrypted form of plaintext.