The correct answer is D. rostopic bw.
rostopic bw is a command-line tool that displays the bandwidth of a ROS topic. It takes two arguments: the topic name and the duration. The duration is the amount of time to run the test, in seconds.
For example, to display the bandwidth of the topic /chatter for 10 seconds, you would run the following command:
rostopic bw /chatter 10
The output of the command will be a line with two numbers: the average bandwidth and the maximum bandwidth. The average bandwidth is the average number of bytes per second that were published to the topic during the test. The maximum bandwidth is the highest number of bytes per second that were published to the topic during the test.
The other options are incorrect because they do not display the bandwidth of a ROS topic.
- rostopic hz displays the frequency of a ROS topic.
- rostopic delay displays the average delay of a ROS topic.
- rostopic echo echoes the messages published to a ROS topic.