Two siblings start from home to go to their respective schools. The brother goes 6 km West, then turns right and goes 3 km and reaches his school. The sister goes 2 km South, then 4 km East, then turns left and goes 5 km and reaches her school. Where is the sister's school with respect to the brother's school?
Options:
1) 10 km West
2) 10 km East
3) 2 km East
4) 2 km West