What is the first step in a DNS lookup?

• A. A user types 'example.com' into a web browser, and the query travels to a DNS recursive resolver
• B. The browser directly queries the root server
• C. The operating system automatically caches the IP address
• D. The DNS server returns an NXDOMAIN

Answer: (A)

DNS resolution starts with the user requesting a domain name, and that request being handed to the system’s DNS resolver. The resolver, typically part of the operating system, then forwards the query to a recursive DNS server to begin resolving the name. This recursive server is responsible for walking the DNS hierarchy (root, TLD, and authoritative servers) to find the IP address. Even if a local cache or hosts file can provide an answer, the initial action in resolving a fresh lookup is sending the query to a recursive resolver. NXDOMAIN is just a possible outcome if the domain doesn’t exist, not the first step.