which among the following statements is TRUE ?
S1 : ( { 0,1,2....(m-1) } , +m ) where +m stands for "addition-modulo-m"
S2 : ( {0,1,2....m} , +m ) where +m stands for "addition-modulo-m".
A) ONLY S1 is a group.
B) ONLY S2 is a group.
C) BOTH S1 AND S2 are groups.
D) NEITHER S1 NOT S2 is a group.