The concepts of Nation-State and State-Nation are important in political sociology and are used to understand how modern countries manage diversity.
A Nation-State generally refers to a political system where:
• One nation corresponds to one state.
• People share common culture, language, ethnicity, or identity.
• Cultural homogeneity is encouraged.
In many classical European nation-states, governments attempted to create a single national identity by promoting one dominant culture and language.
On the other hand, a State-Nation refers to a country where:
• Multiple cultures, languages, religions, and ethnic groups coexist.
• Diversity is recognized and accommodated within one political framework.
• Unity is maintained despite social and cultural differences.
India is often considered a good example of a State-Nation because:
• It contains many languages and religions.
• Different regional identities coexist within one democratic state.
• Constitutional protections help maintain unity in diversity.
The phrase in the question refers to socially and culturally diverse groups remaining together within a single political state.
Option analysis:
• Option (A): Correct because State-Nation refers to culturally diverse groups existing together.
• Option (B): Incorrect because the concept is not about collective rule of states.
• Option (C): Incorrect because central rule is unrelated to the definition.
• Option (D): Partially true regarding coexistence, but it does not fully define the sociological concept.
Therefore, the correct answer is:
\[
\boxed{\text{(A)}}
\]