Where are password representations stored on Linux/UNIX systems?

• A. /etc/passwords
• B. /home/username/.passwd
• C. /etc/passwd and /etc/shadow
• D. /var/log/shadow

Answer: (C)

In Linux/UNIX, password representations are protected by the shadow password mechanism: the actual hashed passwords are stored in a separate file, while basic account information lives in another. Specifically, /etc/passwd holds the user records, and the password hashes themselves are kept in /etc/shadow with restricted permissions so normal users cannot read them. That’s why the best answer lists both locations. The other paths aren’t standard places for password data: /etc/passwords isn’t used, a file in a user’s home directory isn’t the system-wide store, and /var/log/shadow is a log location rather than a password store.