1. Define Directions:

* South is typically represented as negative (-)

* North is typically represented as positive (+)

2. Combine the Vectors:

* 4 km south = -4 km

* 2 km north = +2 km

* 5 km north = +5 km

Total displacement = -4 km + 2 km + 5 km = 3 km

3. Final Answer:

The correct displacement is 3 km north.