Explanation:
The western and central European section of the plain covers all of western and northern France, Belgium, The Netherlands, southern Scandinavia, northern Germany, and nearly all of Poland; from northern France and Belgium eastward it commonly is called the North European Plain.
<u>Answer:</u>
<em>b. Mitchell palmer
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<u>Explanation:</u>
The sequence of raids occuring were called the Palmer Raids. These raids were aimed at capturing the immigrants and deporting them out of the United States. Palmer, the Attorney General, was responsible to lead and carry on the raids. World War I and Russian revolution resulted in fear and rejection for the immigrants in the US. This was named the Red Scare. This fear among the people of the US gave momentum to the Palmer raids. The immigrants and non-residents of the US were referred as aliens. The US Labor Department was upset by these raids as this went against their authority to deport people.
I am pretty sure the answer is population.