The correct answer is B.
A nation is a stable community of people formed on the basis of common language, history, territory and ethnicity. The community occupies a defined territory and is organised under an independent government.
The word nation comes from old French nacion meaning 'birth' or 'place of origin'.
The Cherokee people were a tribe sharing common territory, history, language and customs. They were thus considered a nation.
All the rest of the examples are groups of people joined temporarily without any common territory or shared history.
