Answer : All
1010 is 10 in Decimal A in Hexadecimal
1011 is 11 in Decimal B in Hexadecimal
1100 is 12 in Decimal C in Hexadecimal
1110 is 13 in Decimal D in Hexadecimal
Range of class A Network is from 0-128 in which first Ip and Last Ip address is not used as valid Ip address because they are to serve spacial purpose
First Ip address in class A network Let say 18.104.22.168 it is having a valid no in n/w id and all 0's in host id part which indicates the network id of entire network.
Last Ip address of class A is used as Directed Broadcast Address for Exp : 22.214.171.124