Answer:
The correct sentence is C. " Mass immigration into the United States began in the 1830s, when many Irish, Germans, and Scandinavians arrived. "
Explanation:
Sentence "A" incorrectly implies that the arrival ofIrish, German, and Scandinavian immigrants is merely an example andnot the main cause of the mass immigration of the 1830s;
sentence "B"
incorrectly implies that the arrival of Irish, German, and Scandinavianimmigrants was somehow contrary to the beginning of mass immigrationin the 1830s.
C. Less Food Crops were being grown.
My conclusion, given the paragraph given, is that the Belgians likely made the choice given rubbers value to plant rubber trees instead of food wherever practicable.