What is the correct syntax for adding an IPv4 address to a tag?

The choice indicating 10.0.0.221 represents a valid and correct example of an IPv4 address formatted properly for tagging purposes. When adding an IPv4 address to a tag, it is crucial to ensure that the address follows the standard IPv4 format, which includes four octets separated by periods, each containing a number between 0 and 255.

10.0.0.221 adheres to these criteria, making it a suitable option for tagging. In the context of network management and configurations, such a tag can be utilized to categorize or limit specific network traffic based on the designated IP address, enhancing security and administrative control.

The other options also represent valid IPv4 addresses but may not be the best choices for a tagging scenario depending on the context in which you are adding the address. For instance, while 192.168.1.1 and 127.0.0.1 are valid addresses, they could be less relevant for certain tagging purposes compared to the broader scope of addresses represented by the choice of 10.0.0.221, which is commonly used in local networks and wider deployment scenarios.