The milestone for women's rights that occurred first was D. Women began to earn money by working in factories during the Industrial Revolution.
Women began to work in factories in the early 1800s as the Industrial Revolution was gathering pace in the United States. We see this with the Lowell Factory Girls.
The closest event to this one in terms of women's milestones was the Senaca Falls Convention held in 1848.
Find out more on the Lowell Factory Girls at https://brainly.com/question/22964494.
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