Fill in the blank with a suitable preposition:
They walked _______ the road to the restaurant on the other side, to meet the client.
The preposition ‘across’ is used to speak about moving from one side to the other side of a place or area. In the given context the people are moving from one end on the road to the opposite, therefore ‘across’ is the apt answer. Hence option B is correct. On the other hand prepositions ‘against’, ‘around’ and ‘upon’ are irrelevant in the context. One cannot walk ‘against’ the road since it means to collide with something or walk touching something. Whereas ‘around’ means on every side which is inappropriate since they are crossing the road. While ‘upon’ is used to denote climbing on an object in motion. Thus options A, C, and D are incorrect.