Which tool can you use to monitor bandwidth usage on a MikroTik router?

Traffic Monitor is the correct choice for monitoring bandwidth usage on a MikroTik router. This tool provides real-time statistics and graphical representations of the data flow on the router's interfaces, making it easy to see how much bandwidth is being utilized at any given moment. It can display incoming and outgoing traffic in a detailed manner, allowing network administrators to observe trends and identify potential issues with bandwidth.

The other tools mentioned serve different purposes. Netwatch is primarily used for monitoring the availability of hosts by sending ping requests, rather than directly assessing bandwidth usage. Bandwidth Test is designed to measure the bandwidth between two MikroTik devices but does not provide ongoing monitoring or reporting of actual usage on a continuous basis. Wireless Sniffer is focused on capturing and analyzing packets on wireless networks, which helps in troubleshooting and analyzing network traffic but may not effectively provide an overview of bandwidth utilization.