Final answer:
To determine the topology of a network, the best tool to use would be a Network Mapper, as it provides a visual representation of how the network's nodes are interconnected.
Step-by-step explanation:
If you are a consultant for an IT company and your boss asks you to determine the topology of the network, the best device to use would be a Network Mapper.
A Network Mapper is a tool that can visually map out a network's topology, which includes showing how different nodes are interconnected. It's the most appropriate tool for the task because it provides a clear and detailed overview of the network's structure.
Other options like a Protocol Analyzer, Port Scanner, and Vulnerability Scanner, although useful for other purposes such as analyzing network traffic, identifying open ports, and finding security weaknesses, do not primarily map network topology.