Given the IP address 192.168.10.5 and the subnet mask

Solution

To calculate the valid host address range, we need to understand the network portion and the host portion of the IP address. The subnet mask 255.255.255.240 has a /28 prefix (since 240 is 11110000 in binary, which corresponds to 28 bits for the network). This means the first 28 bits are used for the network, and the last 4 bits are used for the hosts. In this subnet, the valid host addresses are from 192.168.10.1 to 192.168.10.14 , as 192.168.10.0 is the network address and 192.168.10.15 is the broadcast address, neither of which can be assigned to hosts. Therefore, the valid host range is 192.168.10.1 to 192.168.10.14 . Why Other Options Are Incorrect:

• A) This option misses the full range of valid addresses and incorrectly includes 192.168.10.1 , which is valid, but fails to cover all valid host addresses in the subnet.
• B) This includes both the network address ( 192.168.10.0 ) and the broadcast address ( 192.168.10.15 ), which are not valid host addresses.
• C) This includes the broadcast address ( 192.168.10.15 ), which is not a valid host address.
• E) This option specifies a range outside the 192.168.10.0/28 subnet, where the valid addresses are from 192.168.10.0 to 192.168.10.15 .