Members will be able to opt-out of surveys if they do not wish to partcipate.You can now turn on a setting saying "Survey Opt-out" from your main community settings screen to enable the member opt-out feature for your community.
If you wish to turn off this feature for a particular project in your community, you could also do so by disabling the toggle (auto-enabled if you have the "Survey Opt-out" setting turned on for the community) displayed while distributing the survey in your community.
You can enable this feature by going to community settings page and following the steps below: