Respuesta :
work = force x distances
A - moving 2 newton's up 0.6 meter = 1.2 joules
B - moving 4 newton's up 0.6 meter = 2.4 joules
C - moving 6 newton's up 0.3 meter = 1.8 joules
D - moving 9 newton's up 0.3 meter = 2.7 joules
The greatest amount of work is in example D.
D is your answer.