The correct answer is option 1: Article 343. According to Article 343 of the Indian Constitution, Hindi in the Devanagari script is declared as the official language of the Union. This means that Hindi is the language that is used for official purposes, including legislation, administration, and communication at the national level.

Option 2: Article 243 is incorrect. Article 243 of the Indian Constitution pertains to the composition and powers of the Panchayats in the states.

Option 3: Article 223 is incorrect. Article 223 of the Indian Constitution deals with the appointment of additional and acting Chief Justices of High Courts.

Option 4: Article 123 is incorrect. Article 123 of the Indian Constitution grants the President the power to promulgate ordinances during the recess of Parliament.

Therefore, the correct answer remains option 1: Article 343.