The answer is (D) Non of the above. Like Phineas Fogg, you forgot to allow for the rotation of the earth during your journey. Its either 13.58 mph or 13.92 mph, depending on whether you travelled East or West.
It is a book, and there is also a series with Micheal Palin of monty python fame who follows the rout taken by Philious Fogg in the book.
That sounds like fun