Explanation:

Let’s break this down:

- Abhinav runs 12 km west, then 16 km north, making a right-angled triangle.

- Distance from his house = hypotenuse = v(12² + 16²) = v(144 + 256) = v400 = 20 km.

- His final direction from the starting point is towards the North-West (since he went both west and north).

- Let’s check the options:

- 13 km South -- Incorrect, he never went south.

- 13 km North -- Incorrect, wrong distance and direction.

- 15 km West -- Incorrect, wrong distance and direction.

- 20 km North-West -- Right distance and direction.