CompTIA Network+ (N10-007) — Question 282

A host has an IP address of 172.28.57.144 and is on the 172.28.57.128 subnet. Which of the following is a correct subnet mask of the host?

Answer options

• A. 255.255.255.0
• B. 255.255.255.192
• C. 255.255.255.240
• D. 255.255.255.248

Correct answer: B

Explanation

The correct subnet mask is 255.255.255.192, which allows for 64 addresses (from 172.28.57.128 to 172.28.57.191) in the subnet. The other options either provide too many or too few addresses for this subnet, making them unsuitable for a host with the specified IP address.