The 'resolvectl' command is used to query and change the system resolver settings, typically provided by the systemd-resolved service. It effectively allows users to manage DNS settings, such as querying DNS records or changing the DNS server used by the system. Answer A is correct because it directly pertains to managing DNS resolution on the system, which is the primary role of 'resolvectl'. Answer B is incorrect because 'resolvectl' does not manage the enabling or disabling of network interfaces; 'ip' or 'ifconfig' would be used for that. Answer C is incorrect because 'resolvectl' does not provide the functionality to monitor network traffic, which would be accomplished with tools like 'tcpdump' or 'wireshark'. Answer D is incorrect as it describes a function of 'networkmanager' or 'nmcli', not 'resolvectl'.