Manufacturing equipment is related to products as road is related to transportation.
I think that one way to analyze this sentence and arrive to the conclusion that transportation is the option missing in the blank is by thinking that manufacturing equipment is employed with thw purpose of to creating products
; so, in the case of road, it is used in an attempt to distribute or transport. Thus, I figured out that the answer is transportation.
When refering to transportation, I mean to cars, buses, and the like.
