The writer wishes to add a relevant example to Paragraph 2 without straying from the purpose of informing the reader as to how advantageous using the Metro is. Which of the following alternatives does that best?

F. I once made a trip from the end of one line to the end of another, with three transfers in between. I can’t imagine how expensive such a taxi ride would have been!
G. I always purchase a day pass for unlimited trips. When I am in Paris, I want to cram as much sightseeing as possible into my schedule.
H. I once accidentally got on a train going the wrong direction, but I simply transferred trains and was on my way to the Notre Dame.
J. If you buy an unlimited day pass, be careful not to lose it. If you do, you will be forced to purchase a whole new ticket!