When you hand it in
When you hand it in, you self-validate your authorship by showing what you know about your own work.
What it asks
That you wrote it.
That you can show you understand it. You may be asked about your own work: what you argued, why you chose a source, how you reached a conclusion.
That it's continuous with your other writing. That this reads like you.
The same for all students
When your educator switches it on for an assessment, every student in that assessment takes the same step. No one is selected. You show what you know, the same as everyone else in the class.
Everyone in the assessment, on the same footing. No one is singled out by taking part.
What happens next
If you're asked for Further Validation, you're told which part of your work wasn't established and why, and you're offered further ways to show your understanding. You can submit anyway. Your educator makes the final judgement, with your work in front of them.