Final answer:
Canada adopted the Clan System from the aboriginals, which functions as a governance structure, playing a key role in community decision-making and leadership.
Step-by-step explanation:
The system that Canada adopted from the aboriginals is the Clan System, which serves as a governance structure. Indigenous people view self-government as essential for preserving their culture and attaining more control over their affairs. The Clan System's functions involve governing the social structure of the community, including decision-making and leadership roles. This system was among the various forms of governance existing among Indigenous groups before European settlement and was noted for its democratic nature.