Why is March 25, 1911, one of the most important dates in labor history?

It is when the economy significantly turned around for the next century.
It is when one of the largest industrial accidents in the United States occurred.
It is when the labor laws changed significantly.
It is when labor equality became a definitive policy.

The correct answer is: It is when one of the largest industrial accidents in the United States occurred.

March 25, 1911, is significant in labor history because it marks the date of the Triangle Shirtwaist Factory fire, one of the deadliest industrial disasters in American history. The fire broke out in a garment factory in New York City, resulting in the death of 146 workers, mostly young immigrant women. This tragedy highlighted the hazardous working conditions and lack of safety regulations in factories, leading to significant changes in labor laws and safety regulations to protect workers' rights and improve workplace conditions.