The League, like Local 25, had expected a turnout of four or five thousand. They were bowled over by this army, utterly unprepared for it. They had organized strikes in the garment trade, small ones, usually confined to a single shop, but never before had they undertaken something on so vast a scale. They might fail, might be laughed at by the whole of New York as well as John Dyche and the ILGWU men, and all the same they knew this was the challenge they'd been hoping for — their chance to show the world they were more than highbrow butters-in, just as the shirtwaist makers were more than irresponsible little girls. What conclusion can be drawn by connecting knowledge of the historical time period with information in the text?

3. By providing an organizational structure for working women, the Women’s Trade Union League gained enough strength in numbers to have some power.

Explanation:

Joan Dash's "We Shall Not Be Moved," tells the dramatic story of how the women's union led a massive strike in the history of America. The story of women workers protesting and organizing strikes, women activists working towards ensuring better and equal opportunities to their female counterparts became one of the most important events in labor history.

In the given passage, the narrator recounts how women trade union "organized strikes" that were big, bringing a turnout of "[an] army" totally unexpected by the League. The strike was to show the men or the government as a whole that "they were more than highbrow butters-in, just as the shirtwaist makers were more than irresponsible little girls."

This detail gives the conclusion that the organizational structure of the working women shows how the Women's Trade Union League managed to gain enough strength in numbers to assert their ability and power.

Thus, the correct answer is option 3.