(A) In IPv4 addressing, a block of address can be define as $x.y.z.t/n$ in which $x,y,z,t$ define one of the address and $n$ define the mask

(B) The first address in the block can be found by setting the rightmost $32-n$ bits to $0$s

(C) Address of class C is used for multicast communication

(D) There are five classes in IPv4 address

(E) Supernetting combine several networks into one large network

Choose the correct answer from the options given below :