The correct answer is C. Young children were kept from working in factories.
Summary: During the Industrialization years (1870-1916) child labor was business as usual condition. Child labor made up around 20% of the workforce. According to 1900 Census, a total of 1,752,187 (about 1 in every 6) children between the ages of 5 and 10 were engaged in "gainful occupations" in the United States. Their parents had no choice to send them to work as their meager wages helped to support the families. The working children had no time to play or go to school, and little time to rest.
The intention of the Keating-Owen Child Labor Act of 1916 was to restrict and limit the number of hours worked by children in the factories and mines. The law did not apply to children who worked on farms. This Labor Act prohibited "the sale in interstate commerce of goods produced by factories that employed children under 14 years old", "the sale in interstate commerce of goods produced in mines that employed children younger than 16 years old", "the sale in interstate commerce of goods produced in any facility where children under 16 years old worked at night or more than 8 hours per day", and "gave the authority to impose fines on factories that violated the law". It was declared unconstitutional by the Supreme Court on the grounds that child labor was not interstate commerce and therefore only states could regulate it. However, a new program of federal regulation in industry began with this Labor Act.