Answer: A) 3
Step-by-step explanation:
For example : 1) When we divide 21 by 4 , then the remainder is 1.
Therefore we say that [tex]21\ mod\ 4 =1[/tex]
2) When we divide 10 by 7 , we get 3 as remainder.
Then , we say [tex]10\ mod\ 7=3[/tex]
The given problem : [tex]57\ mod\ 6[/tex]
When we divide 57 by 6 , we get 3 as remainder [as [tex]57=54+3=6(9)+3[/tex]]
Therfeore , [tex]57\ mod\ 6=3[/tex]
Hence, A is the correct option.