In DNS name resolution, which sequence describes the path from client to authoritative servers via a recursive resolver?

• A. Client queries resolver; resolver asks root servers, then TLD servers, then authoritative servers; result is cached and returned to client.
• B. Client queries root servers directly without resolver
• C. Resolver queries the IP address block
• D. The client uses only local cache

Answer: (A)

When a client needs a domain’s IP, it hands the query to a recursive resolver. That resolver carries the lookup out for the client. It starts at the root nameservers, which respond with a referral to the appropriate top-level domain (TLD) servers for the requested domain (such as .com, .org, etc.). The resolver then queries that TLD server, which in turn refers it to the domain’s authoritative nameservers. The resolver finally asks the authoritative server for the definitive answer, obtaining the IP address. The resolver caches this result and returns the IP to the client. This path—root, then TLD, then authoritative—is how DNS resolves names through a recursive resolver. The other options don’t describe this collaborative traversal through the hierarchy or rely solely on local cache, which isn’t how standard DNS resolution operates.