you are basically just comparing the ratios (the ratios will have to be the same for both for it to be the correct answer)
so for choice A you would do:
116.5cm:845km =0.14
174cm:1160km=0.15
these are not equal so it would not be correct
the correct answer would be B because:
42.25cm:845km=.05
58cm:1160km=.05