Concept:A nation is defined by the shared identity of its people, not by physical or legal structures.
Explanation:A nation is a group of people united by common descent, history, language, or culture.
These shared features create a sense of belonging and togetherness.
Military strength, population size, and a constitution are features of a state, not a nation.
Therefore, a nation is best identified through its common language and culture.
Answer:B. common language and culture