so i'm going to try my hardest to type this out.

Question

which of the following system of forces provides the block the highest net force?

a.) 11N--->[box]<---71N

b.) 405N--->[box]<---403N

c.) 227N--->[box]<---153N

d.) 22.7N--->[box]<---15.3N

I thought this was super easy, thinking all you had to do is subtract the forces. then the answer would be 'C' with 74N as the net force.

but i got it wrong. my teacher said it was A. how is that so? 'A' only has a net force of 60N.