The correct answer to this question would be alternative B)"Careers."
Career Clusters describe a group of careers within the same industry.
Career Clusters are, as described, a group of careers, that can be divided into categories or areas, such as Agriculture, Food, Natural Resources, etc.
Besides, we can also find careers within these areas. If you take Agriculture, for example, we can find careers within this niche, such as animal trainers, greenhouse managers, dairy farmers, etc.