Final answer:
The rejection of child labor laws challenged the notion of the United States as a progressive and enlightened nation regarding human rights.
Step-by-step explanation:
The labor condition that challenged the notion of the United States as a progressive and enlightened nation regarding human rights was the rejection of child labor laws. The country's failure to pass legislation to protect children from exploitation and unsafe working conditions demonstrated a disregard for the rights and well-being of its youngest citizens.
This labor condition contradicted the idea of progress and enlightenment because it perpetuated a system that placed profit and productivity above the rights and welfare of children. It highlighted the country's hypocrisy in claiming to be a champion of human rights while allowing such harsh and exploitative labor practices.
It is important to note that the other options listed - the passage of women's suffrage, the end of Reconstruction, and the acceptance of some union demands - were all developments that actually contributed to the progress and advancement of human rights in the United States.
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