I believe the answer is: Yangtze river
The three gorges dam is the world's largest power station that built around the Yangtze River. The initial construction of this power station caused the Yangtze river unable to contain the amount of water that it used to be, which led to flooding in areas near that river.
One reason there are very few subsistence farmers left in Africa is because everyone needs cash nowadays. Subsistence farming is when you only plant to feed you and your family. It is hard for the people in Africa to even have money to grow food without selling it to plant more. The correct answer is A.
Things like drug od's and car acciedents