Shivani drives 17 km to the North, then drives 9 km East, and then drives 17 km South.
How far is Shivani from the starting point when considered in a straight line?

The correct answer is 9 km.

Let us trace Shivani's path step-by-step to determine her final position relative to the starting point:

1. First leg of the journey: Shivani starts at a point, let's call it $A$. She drives 17 km to the North, arriving at point $B$. The distance $AB=17\text{km}$ in the North direction.
2. Second leg of the journey: From point $B$, she turns and drives 9 km to the East, arriving at point $C$. The distance $BC=9\text{km}$ in the East direction.
3. Third leg of the journey: From point $C$, she turns and drives 17 km to the South, arriving at her final destination, point $D$. The distance $CD=17\text{km}$ in the South direction.

Since North and South are opposite directions, the 17 km drive South directly cancels out the 17 km drive North in terms of vertical displacement.
This forms a rectangle $ABCD$, where:
- The North-South sides are equal: $AB=CD=17\text{km}$.
- The East-West sides must also be equal: $AD=BC=9\text{km}$.

Therefore, the straight-line distance from the starting point $A$ to the final point $D$ is equal to $BC$, which is 9 km.