Answer:
Since -11 is a prime number, we have following possible options:
Factor out 11
1 |11
|11
NoW sets are
[tex]\\ \rm\longmapsto \left\{1,1,-11\right\}[/tex]
[tex]\\ \rm\longmapsto \left\{-1,-1,-11\right\}[/tex]
[tex]\\ \rm\longmapsto \left\{1,-1,11\right\}[/tex]