AMC 12 2003b Problem 1

Which of the following is the same as

$$\frac{2-4+6-8+10-12+14}{3-6+9-12+15-18+21}?$$

$\text {(A) } -1 \text {(B) } -\frac{2}{3} \text {(C) } \frac{2}{3} \text {(D) } 1 \text {(E) } \frac{14}{3}$