Final answer:
To verify a network's transmission speed, use a throughput tester which measures the amount of data that can be transmitted over a network. Connectivity software, bit-error rate tester, and loopback plug have different functions and are not used for this purpose.
Step-by-step explanation:
To verify a network's transmission speed, you should use a throughput tester. A throughput tester measures the amount of data that can be transmitted through a network over a given period of time. It provides an accurate measurement of the network's performance and can help identify any bottlenecks or issues that may be affecting the speed.
For example, if you suspect that your network is not performing up to its full capacity, you can use a throughput tester to determine the actual speed at which data is being transmitted. By comparing the results to the expected speed, you can assess the efficiency of your network.
Other tools mentioned in the question, such as connectivity software, bit-error rate tester, and loopback plug, serve different purposes in network troubleshooting and are not specifically designed to measure transmission speed.