Final Answer:
nmap command lines can be used to scan an entire subnet with nmap.
Thus, the correct answer is option b. nmap.
Step-by-step explanation:
The correct command to scan an entire subnet with nmap is option b. "nmap" without any additional arguments will perform a basic scan on the localhost or the specified target. To scan an entire subnet, you can provide the subnet range as an argument after the "nmap" command.
In the context of networking, a subnet is a range of IP addresses. To scan an entire subnet, you specify the subnet range after the "nmap" command. For example:
nmap 192.168.1.0/24
This command will scan all the IP addresses in the 192.168.1.0 subnet. The "/24" is a subnet mask, indicating that the first 24 bits are the network portion, and the remaining 8 bits are for host addresses.
It's important to note that options a, c, and d do not provide the necessary subnet information or contain syntax errors. Option a, "nmap -30," appears to have a typographical error, and option d, "nmap /*," has invalid syntax. The correct and concise way to scan an entire subnet is to use the basic "nmap" command followed by the subnet range. Therefore, the correct answer is option b. nmap.