Correct Answer - B

`(b)` `x+y+z=-12`

Here `-10 le x`, `y`, `z le -1`

Let `x_(1)=-x`, `y_(1)=-y`, `z_(1)=-z`

`:.` we have `x_(1)+y_(1)+z_(1)=12` , where `1 le x_(1)`, `y_(1)`, `z_(1) le 12`

`:.` Number of solutions of the equation

`=^(12-1)/(C_(3-1)=^(11)C_(2)=55`