Nokia 4A0-100 Exam - Question 46

D. 100.1.1.0/28 Here's the explanation: The given subnets are: 100.1.1.4/30 100.1.1.8/30 100.1.1.12/30 100.1.1.16/30 A /30 subnet mask means 4 IP addresses per subnet (2 usable addresses, 1 network address, and 1 broadcast address). When these subnets are viewed in binary form, they all fall within the range of 100.1.1.0 - 100.1.1.15. The most specific aggregate prefix that includes all these subnets is 100.1.1.0/28, as it covers the address range from 100.1.1.0 to 100.1.1.15, which includes all four /30 subnets.

C. 100.1.1.0/28 is correct 100.1.1.0/28 have addresses from 100.1.1.0-15 but 100.1.1.16/30 has addresses 100.1.1.16-19.