Password protect your survey with an activation code
When you don't want to give away the content of your survey/quiz to anyone, for example when you enclose sensitive information about your company, you can use the Activation Code to protect your survey/quiz. When you choose to use this feature, the Activation Code needed to open the survey/quiz will appear below the title of the feature.
When someone opens your survey/quiz they will see this screen first:
Here the respondents have to enter the Activation Code which you've sent them.