Answer:
B. -1
Explanation:
I just looked over it quickly, everything looks correct.
To see if a number is in the solution set, plug it in and see if its true:
0 - 9 > -10
-9 > -10
true
-1 - 9 > -10
-10 > -10
false
1 - 9 > -10
-8 > -10
true
2 - 9 > -10
-7 > -10
true
The only solution that doesn't work is B. -1