Increases in income inequality in the United States are partially attributed to:

A) equal and rising increases in the salaries of low-wage workers.
B) the impact of technological innovation on the demand for labor.
C) a reduction in the effect of international trade on the economy.
D) stricter immigration policies.

Technological innovation has led to a decrease in the demand for low-skilled labor, which has resulted in lower wages for these workers and higher wages for high-skilled workers. This has contributed to increasing income inequality in the United States. The other options (A, C, and D) are not supported by evidence and are not significant factors in explaining the increasing income inequality in the US.