Which of the following statement regarding email transformation is true?

The statement that only unique emails can be transformed is true because, in Okta, the email transformation process requires that each email address is unique to avoid conflicts. If multiple users were allowed to have the same email transformed into different usernames, it would lead to confusion and potential issues with user identification and authentication within the system. The transformation process is designed to ensure that each transformed username is distinct, which is essential for maintaining the integrity of user accounts and their associated permissions. This uniqueness requirement helps prevent errors in user management and provides a clear structure for identity verification.

In contrast, other options presented do not align with Okta's email transformation rules. The idea that all users could have the same email transformed into different usernames undermines the principle of unique user identities in the system. The notion that transformation is not allowed is incorrect, as Okta actively supports email transformation under specific conditions. Lastly, while having defined formats might help standardize the transformation process, it is not a strict necessity for the transformation to take place, making that option less accurate in the context of email transformation.