Well we know that it is not A or C, Reason: Some states have up to 5m people in it. (For example about 8 live in just new York alone.)
And we also know its not 10 billion. Reason for this: Scientist have proven that there is no more then 8 billion people today.
And so now we got 6.5 billion is the closest, the real number is about 7.5 billion.
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Happy birthday :) have a good day
Answer:
Transportation is the first and main step for trading and trading is a backbone for country's economy, and transportation includes the territory sector of country's GDP.
Hope it helps!
I believe this was the Republic of Turkey.