Explanation:

- Roshni starts at her original point.

- She walks 15 metres north.

- She then turns right and walks 20 metres east.

- Next, she turns right again and walks 10 metres south.

- She turns right once more and walks 20 metres west.

- Now, she is in line with her starting point horizontally but 5 metres to the north.

- Her distance from the original point is 5 metres.

- Option:1 - 5m