What is the main idea of excerpt

Which progressive reform was least related to the causes and effects of world war i? o legislation limiting the use of child labor o establishing 8-hour workdays for railroad workers o reducing tariffs on imported goods o expanding women's rights and the right to vote

Why is it useful for historians to base certain studies on the analysis of historical periods

:) during the cold war, people were afraid of communists, both outside and inside the united states. the red scare and mccarthyism that grew out of these fears were damaging to the american way of life. during the mccarthy years, many of the freedoms guaranteed in the bill of rights were limited. write a paragraph explaining what lessons can be learned from the mccarthy era about what u.s. citizens need to protect in order to preserve the democratic political system and the american way of life.