The domain of the function is possible values of independant varaible such that function is defined or have real values.
So the expression
[tex]\frac{(x+2)(x-3)}{(x-1)(x+6)}[/tex]is not defined for x = -6 and for x = 1, as expression becomes undefined for this values of x (Denominator becomes 0).
So answer is,
[tex]\frac{(x+2)(x-3)}{(x-1)(x+6)}[/tex]Option B is correct.