Which statement is a fact the author uses to support the author's argument?

The author uses the fact that the average American worker’s salary and benefits are declining while the rich get richer to make her case that the government should intervene to ensure that workers get their fair share of the wealth. The facts in (Socialism is in decline) and (The government-controlled economy of the Soviet Union was a failure and collapsed) provide background information but are basically unrelated to the author’s position on the role of government. The author agrees with (Capitalism is an efficient system for economic growth), but this statement isn’t used to support her main argument that government should intervene in the economy.