The correct answer is A. Net.Net.Net.Node.
Class A networks are the largest of the three classes of IP addresses, with a first octet ranging from 1 to 126. The first octet is used to identify the network, and the remaining three octets are used to identify the host. This means that there can be a maximum of 126 Class A networks, each with a maximum of 16,777,216 hosts.
The other options are incorrect because they do not match the addressing format for Class A networks. Option B, Net.Net.Node.Node, is the addressing format for Class B networks. Option C, Net.Node.Net.Node, is the addressing format for Class C networks. Option D, Net.Node.Node.Node, is the addressing format for Class D networks. Option E, None of the above, is incorrect because it does not specify a correct addressing format.