B. Two continental plates colliding
<span>Residents of Mexico City are encouraged to use bicycles to move around the city. This helps ease traffic congestion, allows able bodied people to get to their destination faster, reduces carbon emissions, saves fuel, money and promotes healthy exercise. All in a city that is overcrowded and basically fat. Mexico has an obesity problem and riding a bike to get around a few days a week or more can produce a lot of positive benefits.</span>
<span>had a population of 249.9 million in 2013
and
</span>1,904,569 km2<span> </span>
