The correct option is B 20 N (North)
The given forces are 10 N (North), 10 N (North), 8 N (West) and 8 N (East).
We know that the forces are added if they are in the same direction and they are subtracted if they are in opposite directions.
So, the net force = 10 N (North) + 10 N (North) = 20 N (North) and 8 N (West) - 8 N (East) = 0.
Therefore the net force on the block is 20 N in the North direction.