In CIDR notation , there are 2 things :
a) The addresses allocated to a block are continuous blocks of IP addresses
b) The first address is divisible by number of addresses in a block
So keeping in mind these points , we have :
For representing 224 IP addresses , we need 3 octets to represent..
So 1st address should contain 3 0's in its dotted decimal notation which is not in any of the options..
Hence D) is the correct answer..