Answer:
c. Working conditions became increasingly unbearable.
Step-by-step explanation:
According to a different source, these are the options that come with this question:
a. Their jobs were gradually taken over by men.
b. The advances in mechanization decreased the need for unskilled labor.
c. Working conditions became increasingly unbearable.
d. Too many years working in the mills made them undesirable marriage partners.
The main reason why these girls decided to resign from working in the mills and return to their family farms in the 1840s was that the working conditions at the mills became increasingly unbearable. As more immigrants arrived, and more workers moved to cities, competition for work became more intense. Factories were able to decrease wages, increase hours and be careless about safety standards and continue to get employees. Therefore, the conditions in factories and mills became worse, which forced many people to return to their farms.