Final answer:
The agricultural industry was exempt from the child-labor laws of the Factory Act of 1833, likely due to seasonal demands and the norm of family involvement in farm work.
Step-by-step explanation:
The industry that was exempt from the child-labor laws passed in the Factory Act of 1833 is the c) Agricultural industry. This exemption was likely due to the seasonal demands of farm work and the traditional involvement of family members, including children, in agriculture. Unlike factory work, which was seen increasingly to necessitate regulation due to the growth of industrialization and the urban working-class, farming continued to be viewed as a family-based endeavor where children's labor was considered part of their domestic upbringing and contribution to the family's livelihood. The agricultural industry's reliance on child labor was also less contested because, in contrast to factories, farms typically posed fewer immediate dangers to children's health and had a historical precedent of involving younger family members.