Hot answers tagged google-forms
You can't. With anonymous people filling in the survey there is no way to tell if they have done it more than once. You could have the users enter an email address into the form and then use Google Apps Script to check. However, if they enter a different email address you are back to square one.
As Rubén said, conditional formatting is for human consumption only: neither sheet formulas nor scripts can access it. You should create a column that records the fact of "all answers are correct", and then filter by that column. For example, put in E2 =arrayformula((C2:C=2)*(D2:D=4)) which will put 1 in every row where both answers are correct. Then ...
You can apply unique id to each link you send out, using pre-filled links. Add one more field to the form, e.g., "user token". Follow the instructions for getting a pre-filled link, entering something like "qwerty" in the "token" field. Inspect the pre-filled link that you get: it will look like https://docs.../viewform?entry.123456789=qwerty (there may ...
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