Question

the us population grew during the gilded age mainly because of
the need for skilled laborers.
the growth of agriculture.
a decline in settlement of the west.
a sharp rise in immigration.

Explanation:

During the Gilded Age (late 19th century) in the US, industrialization led to a high demand for labor. This period saw a massive influx of immigrants from Europe and Asia, which was the primary driver of population growth. The need for skilled laborers was not the main reason (many immigrants were unskilled), agriculture growth was not the primary population - growth driver, and settlement of the West was increasing, not declining. So the main reason for population growth was a sharp rise in immigration.

Answer:

D. a sharp rise in immigration