Which server is contacted first during DNS resolution?

• A. Root name servers
• B. TLD name servers
• C. Authoritative name servers
• D. Resolver

Answer: (A)

DNS resolution starts at the top of a hierarchy. If there’s no cached answer, the resolver’s first step is to query a root name server. Root servers don’t hold the final records for a domain; instead, they know which server handles the top-level domain (like .com, .net, or .org) and direct the resolver there. That referral lets the resolver continue down the chain—from root to the appropriate TLD name servers, and then to the domain’s authoritative name servers that provide the actual IP address. So the root name server is contacted first because it serves as the starting point that guides the resolver to the correct authority for the domain. If the answer is already cached locally, the resolver can answer without contacting any upstream server.