You registered contoso.com and created a public Azure DNS zone named contoso.com. What must you update so the records in that Azure DNS zone are resolvable from the internet?

To make your Azure DNS zone resolvable from the internet, you must update the Name Server (NS) records at your domain registrar. When you create an Azure DNS zone, Azure provides a set of dedicated NS records. These records tell the internet where to find the authoritative DNS servers for your domain (in this case, Azure DNS). By updating your domain registrar's NS records to point to Azure's NS records, you delegate control of your domain's DNS resolution to Azure. Creating NS records in contoso.com or modifying the SOA record in either location would not delegate authority from the registrar to Azure DNS. The SOA record defines the start of authority for a zone, but NS records are responsible for delegation.