We understand that event hosts sometimes want their invitees to agree to certain terms and conditions before they submit their registration. The event's terms and conditions agreement typically includes the terms, the rules, and the guidelines of acceptable behavior and other useful sections to which the invitees must agree in order to attend the event.
The use of this custom question type is very simple: add it to your form as it is any other custom question and populate the fields with the question, description - which is optional, legalese text and confirmation text. Select the way you want your invitees to answer the question - as a group, individually, or only if no one in the group indicates they are attending. Unlike other custom question types, you can't toggle off the answer requirement for this one. Your invitees won't be able to pass this question when completing the registration form without entering an answer/consenting to the terms of your event.
Here's a quick screencast of adding this custom question type to your form: