问题详情

Thanksgiving Day, which originated in America, was first celebrated by the pilgrims after they had achieved a bumper harvest to show their gratitude to God and the Indians. Since 1863, it is celebrated on______.
A．November 31st
B．December 11th
C．the fourth Thursday of November
D．the fourth Thursday of December请帮忙给出正确答案和分析，谢谢！