Which of the following is NOT relevant to a user exercising their data portability rights?

 Notice and consent for the downloading of data (A): Users must be informed and consent to the downloading of their data. Reference: GDPR Article 20(1).

 Detection of phishing attacks against the portability interface (B): Ensuring the security of the data portability process is crucial, including detecting phishing attacks. Reference: GDPR Article 32.

 Re-authentication of an account, including two-factor authentication as appropriate (C): Re-authentication is necessary to ensure that the data is being ported securely and to the correct person. Reference: GDPR Article 20(2).

 Validation of users with unauthenticated identifiers (e.g., IP address, physical address) (D): Data portability requires authenticated identifiers, and using unauthenticated identifiers is not relevant or secure. Reference: GDPR Article 20.