The verified Digital Signature will ensure that a legitimate respondent is filling out the survey. The authenticity of the respondent is ensured by an email verification step, without which he/she cannot advance to the next step in the survey. Apart from that a PDF for every response is generated and stored in responses and the user will have the option to send the response PDF to the respondent via an auto email delivery system.
The Verification Signature needs to be added as a Question Type.
This feature is available with the following license :