A. Cash crops such as tobacco and sugar required many workers.
The correct answer is: An asteroid impact.
The scientists call it the extraterrestrial impact theory. It states that a giant, six mile wide meteor hit the Earth around 66 million years ago. As a consecuence, clouds of iridium dust and other materials were thrown into the air, blocking the sunlight for years. This lead to the extintion of the dinosaurs who were not able to feed themselves as plants didn't grow. Photosynthesis was not possible and food chains could not be completed. When the dust settled the greenhouse gases were locked in the atmosphere causing a general increase of temperature.
The answer is black freedman who left the south to seek opportunity in kansas
