Question

the main, or central, idea of the passage is because of the triangle shirtwaist factory fire, the government began to regulate working conditions in factories. how does the detail in bold develop the main idea?
the early twentieth century was a difficult time for new york city’s garment workers, many of whom were immigrant women who worked long hours in dangerous factories for poverty - level wages. after the garment workers went on strike in 1910, some factory owners improved their workplaces and allowed employees to join unions. the triangle shirtwaist factory was a notable exception: the owners resisted a union and continued to maintain shoddy working conditions. on march 25, 1911, a fire broke out at the factory. many workers were trapped inside; the rickety fire escape collapsed, and the only accessible exit had been locked. in all, 146 workers perished. the tragedy sparked public outrage about labor injustices, and citizens pressed their government to take action. consequently, over the next few years, new york’s legislature passed many laws designed to improve workplace safety.
it highlights the proposed changes to unsafe working conditions.
it compares conditions in the triangle shirtwaist factory before and after laws were passed.
it identifies the conditions that led to the great loss of life in the fire.

Explanation:

The main idea links the Triangle fire to government regulation of factory working conditions. The bold detail describes trapped workers, collapsed fire escapes, and locked exits—specific unsafe conditions that caused 146 deaths. This tragedy sparked public outrage, pushing the government to act. Thus, the bold detail identifies the conditions leading to mass fatalities, which directly motivated regulatory changes.

Answer:

It identifies the conditions that led to the great loss of life in the fire.