Should act like the Consent / Agreement type question, in that there is a checkbox for user to tick, but instead to be for users to opt in or opt out of mailing lists, for example, so they can leave the checkbox unchecked and still proceed through the survey, unlike the Consent / Agreement which is always mandatory to place tick in checkbox. Also, so this can be used in conjunction with HubSpot forms module.
Only other option is a Yes or No type question, but a checkbox would be preferable and is more elegant.
