Final answer:
In December of 1921, a Potlatch would have likely experienced increased participation, as it was a cornerstone event for Pacific Northwest groups to display status and share wealth through hospitality. The correct option is C.
Step-by-step explanation:
In December of 1921, a Potlatch likely experienced increased participation. A Potlatch is an important socio-political ceremony among Pacific Northwest groups, where wealth was shown through generosity and giving, with the hosts distributing gifts, providing food, and entertaining guests.
The ceremony was central to demonstrating the host's status and social rank, with a successful Potlatch potentially elevating a person's or family's status. Considering the cultural significance of the Potlatch, it was an event where people wanted to attend and participate, thereby increasing their connection with the community and reinforcing the social hierarchy.
Hence, Option C is correct.