QTI 2.1: visibility key must be changed

A test has a manual correction, which means that the result is not visible directly. do the test once, change visibility to result is visible. do the test the second time --> see screenshot
when you click on the course element, it disappears.

--> add other wording
The result is not yet visible. The visibility need to be changed by the coach.
Das Resultat ist noch nicht sichtbar. Die Sichtbarkeit muss vom Betreuer geändert werden.