Good question. What they mean to say is that locations that are "more East" are earlier, while locations that are "more West" are later.
The starting city was at a longitude of 75* West. Notice that 73* West is more to the East than the starting city (in other words, it is "less West"), while 78* West is more to the west than the starting city.
This is why we subtract 8 minutes going to 73* West from 75* West.
As a whole, Globalization is trying to unify the world together, by integrating people, currency, and governments in hopes of greater interaction levels, so, I say it is D.
I agree with Northeast, the big cities are probably because the first American colonies were in the northeast and with those came colleges like Harvard, Princeton, Yale, MIT, etc.