Exam ANS-C00 topic 1 question 140 discussion

B B B B https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/hosted-zone-public-considerations.html Reusable delegation sets By default, Route 53 assigns a unique set of four name servers (known collectively as a delegation set) to each hosted zone that you create. If you want to create a large number of hosted zones, you can create a reusable delegation set programmatically. (Reusable delegation sets aren't available in the Route 53 console.) Then you can create hosted zones programmatically and assign the same reusable delegation set—the same four name servers—to each hosted zone. Reusable delegation sets simplify migrating DNS service to Route 53 because you can instruct your domain name registrar to use the same four name servers for all of the domains for which you want to use Route 53 as the DNS service. For more information, see CreateReusableDelegationSet in the Amazon Route 53 API Reference.

B. Reusable Delegation Sets By default, each hosted zone that you create gets a different set of four name servers—a different delegation set. If you create a lot of hosted zones, maintaining different delegation sets can be difficult and time consuming. Route 53 lets you create a delegation set that you can reuse with multiple hosted zones. See Reusable delegation sets.

Answer B Why To make it easier to migrate DNS service to Route 53 for a large number of domains, you can create a reusable delegation set and then associate the reusable delegation set with new hosted zones. Refer - https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/route-53-concepts.html#route-53-concepts-reusable-delegation-set

CCCCCC Import domain that bought from another registrar