Why does immigration most likely continue to increase the U.S. population?

Question

The U.S. economy benefits from immigrant labor.
Immigrants are needed as soldiers in the U.S. military.
The U.S. government seeks out immigrants to combat falling birth rates.
Immigrants easily transition into life in the United States.

Son says D, I think it's A.

Answer 1

I agree, but he looks at the world through rose colored glasses. Thank you!

Answer 2

I don't like any of the answers. Adjusting to American life or adding to our labor force says nothing about increasing the population.

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