The correct answer to the first question is:
b) International Labor Organization
The International Labor Organization (ILO) actively works to combat child labor globally.
As for the phrase "circulated children," it is generally associated with the historical phenomenon of child labor, where children were often moved between different locations for work, sometimes referred to as "circulation." This could refer to the practice of employing children in various industries, moving them from place to place to meet labor demands, often with little regard for their well-being or education. If you're looking for a more specific context, please provide that, and I can give a detailed explanation!