When you setup a Mythos Survey, you have the option of allowing survey respondents to receive a copy of their survey response via email. This option is enabled by default so you only need to uncheck this option if you DO NOT want your survey respondents to be able to get a copy of their submission.
When this option is enabled, the Mythos Survey confirmation page will display an option that allows the survey respondent to enter their email address to receive a copy of their survey submission.