Right answer: la ventanilla
If you travel by plane, you should know that there are pressurized windows through which you can see if you want, there are also three basic types of saets, those near the corridor, those in the middle and those near the window.
Knowing this and that in the sentence the verb mirar (to look) is used, in this context the correct option is ventanilla (window).
Then, the complete sentence is:
Durante el vuelo, me gusta mirar por la ventanilla
During the flight, I like to look through the window
The options el teléfono (the pone), el asiento (the seat) and el viaje (the trip) are incorrect because do not match with the context of the sentence.
