Which of these quotations from "The Immigrant Contribution" best supports the answer to Part A? A. Between 1880 and 1920 America became the industrial and agricultural giant of the world as well as the world's leading creditor nation. This could not have been done without the hard labor, the technical skills and the entrepreneurial ability of the 23.5 million people who came to America in this period.
B. [Immigration] is the expression in action of a positive belief in the possibility of a better life. It has thus contributed greatly to developing the spirit of personal betterment in American society and to strengthening the national confidence in change and the future.
C. [Immigration] reminded every American, old and new, that change is the essence of life, and that American society is a process, not a conclusion.
D. [Immigration] infused the nation with a commitment to far horizons and new frontiers, and thereby kept the pioneer spirit of American life, the spirit of equality and of hope, always alive and strong.