Correct Answer. A. netstat -a netstat -a displays all connections and listening ports, including the status of TCP and UDP ports, which is essential for verifying if a server is listening on specific ports such as HTTPS.
Option B is incorrect. netstat -r displays the routing table, which doesn't provide information about active connections or listening statuses.
Option C is incorrect. netstat -e displays Ethernet statistics, which include network data but not details on specific listening ports or connection statuses.
Option D is incorrect. netstat -s shows per-protocol statistics, helpful for diagnostic purposes but not for checking specific listening ports or active connections.