Answer:
D. Immigration provided the human resources. More than that, it 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 hope, always alive and strong.
Step-by-step explanation:
Pathos which is the appeal to emotion is used to elicit the feelings of compassion or pity which are innate in people. Stories and passionate appeals are used by writers to achieve this.
In the last option, the pioneer spirit of America was referenced by the author to appeal to the emotion of unity and peace that was fostered on Americans through immigration.