Divide as Indicated or State That the Division Is Undefined $\frac { - 168 } { 7 }$

Divide as indicated or state that the division is undefined.
- $\frac { - 168 } { 7 }$

A) $- 24$
B) $- \frac { 1 } { 24 }$
C) $- 34$
D) 24