Fill in the blank with a suitable preposition.
Please book the seats _______ our app.
The preposition ‘through’ is used to denote a means via which something can be done. In the given sentence people use the app to book the seats, hence option D is correct. The preposition ‘by’ is used to refer to the agent or the person who performs the action. Since the sentence speaks about a way and not about the people option A is incorrect. On the other hand, ‘for’ is used to show who is meant to have or use something. This is not apt here because the 'app' is not a person, for whom the seats are booked. The 'app' is used to book the seats. Therefore option C is incorrect. Similarly ‘of’ is inappropriate here because it denotes belonging. The seats don’t belong to the app, therefore, option B is incorrect.