Answer:
I would assume that it is C. Africa
Explanation:
This is because, if you look at the map, a large portion of Africa is deemed as an area with economic water scarcity. The other regions of Africa is listed as not estimated and approaching water scarcity.
He ends up back at the starting point because if he walks the same steps forwards and backwards he would be in the same spot
Brick
Straw
They began trade with other people to create money and get new crops