They are found in lake Maracaibo.
I think the answers are:
- <span>There are more public transportation options.
- </span><span>It is easier to get from one place to another.
The main form of transportation in cities is either Buses or Trains, so we can eliminate options B and most of the main streets in big cities are actually designed for pedestrians, so we can eliminate option A.</span>
Either on the bottom of the earth or the top.