The question asks about the distance from the boy's original position after he walked in two perpendicular directions. Let’s analyze this step-by-step.

1. Setup:

   • The boy turns 90 degrees, forming a right angle in his path.
   • He walks 12 km in one direction and, after turning, continues another 12 km in the perpendicular direction.

2. Calculation: Since the two legs of his journey form a right triangle, with each leg being 12 km, we can use the Pythagorean theorem to find the hypotenuse $c$, which represents the straight-line distance from his starting point: $c = \sqrt{12^2 + 12^2} = \sqrt{144 + 144} = \sqrt{288} \approx 16.97 \text{ km}$

3. Answer: Rounding to the nearest kilometer, the answer is approximately 17 km. However, based on the choices given in the image, the closest answer provided is 16 km.

Would you like a breakdown of this solution or further explanation?

Here are some follow-up questions to expand on this problem:

1. How would the answer change if the boy walked different distances in each direction?
2. What if the boy turned by 45 degrees instead of 90 degrees after the first segment of his walk?
3. Can you use trigonometric functions to verify the distance calculated here?
4. How is the Pythagorean theorem applied when finding distances on a coordinate plane?
5. What if there were three turns, each with a different distance? How would you calculate the final position?

Tip: When dealing with paths forming right angles, always think about the Pythagorean theorem if you're asked for a straight-line distance.