How can I confirm I've answered a questionnaire correctly?

In the app

After completing the questionnaire, you can see at the bottom in the "TO-DO's" section that your questionnaire is completed.
If you want to view this several days after completing the questionnaire, go to "Timeline", here you can see when you've completed the questionnaire.

If the questionnaire isn't completed yet you wil be able to still open the questionnaire in the "TO-DO's" section. You can also see the progress of your questionnaire.

On web

On the tab Questionnaires you can see your past questionnaires, these are already fully completed.
You can also see your pending questionnaires and their progress.