Question

what factor helped cause the great migration?
world war i increased demand for industrial labor in northern states.
the military opened large bases in the south to prepare for world war ii.
the supreme court ruled that racial segregation was unconstitutional.
president wilson offered free or low - cost housing.

Explanation:

The Great Migration (early 1900s-1970s) saw millions of Black Americans move from the South to the North. World War I created a shortage of industrial labor in Northern factories as European immigration slowed, drawing Southern Black workers seeking jobs and better opportunities. The other options are incorrect: WWII occurred long after the start of the Great Migration, the Supreme Court's segregation ruling (Brown v. Board) was in 1954 (late in the migration period), and President Wilson did not offer such housing.

Answer:

A. World War I increased demand for industrial labor in northern states.