What might indicate a computer's assigned MAC address?

A MAC address, or Media Access Control address, serves as a unique identifier for a network interface for communication on the physical network segment. Every network device, such as a computer or smartphone, is assigned a unique MAC address that helps in identifying it on a local network. This address is hardcoded into the network interface card (NIC) by the manufacturer, ensuring that no two devices on the same network can have the same MAC address.

In contrast, the other options do not provide unique identifiers for network interfaces. Internet speed, operating system version, and software applications installed on a computer are not linked to its network hardware identification. They represent performance characteristics, system attributes, and functionality but do not pertain to the unique identification mechanism used in local area networking. Thus, the correct option accurately captures the essence of what a MAC address represents.