Fill in the blank: To manage rate limits, ___ enroll contacts as they meet certain criteria.

In the HubSpot Data Integration certification, webhooks are the correct answer because they allow for real-time data synchronization by automatically "enrolling" and pushing contact data to an external system the moment specific criteria are met or an event occurs. Unlike polling, where an integration must repeatedly ask HubSpot for updates—often wasting API calls and hitting rate limits—webhooks are event-driven, ensuring that data is only sent when necessary. This push-notification model is a highly efficient way to manage rate limits because it eliminates redundant requests and ensures the external system stays updated using the minimum number of transactions required for the specific contacts that triggered the action.