The nineteenth-century emigration of a large number of Swedes from a particular region of Sweden to Isanti County, Minnesota, as a result of communications from friends and relatives who preceded them there is an example of

Can you maybe send me a screen shot of the map? it would really me you. : )

The answer would be a.

Genetically modified corn is a very controversial issue because of the potential benefits that it can bring, but also the potential for it to bring problems in the future. genetically modified corn can be beneficial in the developing world because it can be modified to be resistant to drought, or pesticide, and therefore the crop is stronger and easier to grow. however, the use of gmo corn can also be problematic because they decrease the diversity in the types of seeds that are used to grow food and also can make farmers dependent on the seeds from companies because they can only be used once to grow corn. 

Some of the great contributes to advancement in the us were immigrants