You can include HTML links in an email to give consumers the option to opt in or opt out of receiving messages.
When a consumer clicks either link, the action applies only to the email address that received the message.
Opt-in Link
The opt-in link allows the consumer to consent to receiving future messages at their email address:
<a href="${primaryDemographicEmail.optInUrl}">Opt In</a>
Opt-out Link
The opt-out link allows the consumer to unsubscribe from future messages at their email address:
<a href="${primaryDemographicEmail.optOutUrl}">Opt Out</a>