The government’s total war effort during times of conflict, such as World War II, typically had a significant positive impact on the economy, including in Washington. The most accurate choice would be:
It boosted the economy and led to new manufacturing jobs.
Government mobilization for war often results in increased production and job creation, particularly in industries related to defense and manufacturing. This can also lead to an overall economic boost in the region as more jobs become available and people engage in wartime work.