Concept:According to the Indian Constitution, Hindi in Devanagari script is the official language of the Union.Explanation:Article 343(1) of the Constitution declares Hindi as the Official Language of the Union.Article 343(2) allowed the continued use of English for official work for 15 years after the Constitution commenced.The Official Language Act later made English an associate official language, but Hindi remains the primary official language.Therefore, Hindi is not the national language, nor associate official language, nor classical language.Answer:B. official language