Final answer:
Option (d), Agricultural workers on a farm are often exempt from the minimum employment age due to child labor law exemptions for family-owned farms and agricultural activities involving parental consent.
Step-by-step explanation:
The job likely to be exempt from the minimum employment age is d) Agricultural worker on a farm. Generally, there are exemptions to child labor laws for family farms and children working on farms with their parents' consent. This exemption is based on a traditional understanding that farming can be a family activity where children can safely participate and contribute to the family business under certain conditions.