Refer to the exhibit. A network engineer must provide configured IP addressing details to investigate a firewall rule issue. Which subnet and mask Identify what is configured on the eth0 interface?

10.8.0.0/16 defines a much larger network (255.255.0.0) that is too broad if a /19 mask is configured on the interface.

10.8.64.0/18 (255.255.192.0) defines a subnet range that begins at 64 in the third octet and does not include 138.

A /19 subnet mask (255.255.224.0) means the first 19 bits define the network portion; for an IP address such as 10.8.138.X, the binary representation of 138 (10001010) reveals a network portion of 100 in the third octet, which is 128 in decimal, correctly identifying the network address as 10.8.128.0/19.

10.8.138.0/24 defines a network where the third octet is entirely part of the network address, which contradicts the /19 mask implied by the correct answer.