Which sequence correctly represents the order of DNS servers consulted by a resolver?

• A. Root -> TLD -> Authoritative
• B. Authoritative -> Root -> TLD
• C. Root -> Authoritative -> TLD
• D. TLD -> Root -> Authoritative

Answer: (A)

A DNS resolver resolves a name by walking the DNS hierarchy from the top down. It starts with root servers, which don’t hold host records but point you to the appropriate top-level domain (TLD) servers for the domain’s suffix (like .com, .org). The resolver then queries that TLD server, which in turn refers it to the domain’s authoritative servers—the ones that actually hold the DNS records for that domain. The authoritative server returns the requested IP address (or a negative result), completing the lookup. In practice, caching can skip steps on follow-up queries, but the logical order remains root, then TLD, then authoritative. The other sequences skip or reorder these referrals in a way the DNS hierarchy doesn’t support.