The correct option is B Roads can be built in most terrains
Construction of roads is a lot cheaper than construction of railways.
Unlike railways, undulating topography is not a major barrier for construction of roadways. Mountainous regions and uneven land is not a major barrier for road construction.
It is a lot easier to have reliable road transport rather than rail transport in areas with low population. It is cheaper to run a bus to transport a smaller number of people. If the volume of goods to be transported is less, road transport is a better option.
Unlike roads, railways cannot provide door to door connectivity. You have to travel from the railway station till your home by road. The same is applicable to goods as well.