Answer:
Young children below the minimum age were working.
Explanation:
As can be seen from the given excerpt, not only is the living condition unsuitable for anyone to be living in. Moreover, young children, as young as five were made to work despite the "law rigidly exclu[ding] them from such occupations in the factories." Though tenement workers would want to get as much work done as possible, the law rigidly prohibits the inclusion of young children to work in the factories. But as seen in the document, this law is not adhered to, and young children under the age of 10 were made to work till "eight o'clock in the evening."
Thus, the correct answer is the second option.