With reference to the administration of Delhi Sultanate, which of the following was the department of State Correspondence ?

Diwan-i-insha

The correct answer is Option 4 - Diwan-i-insha

In the Delhi Sultanate administration, the department of State Correspondence was the Diwan-i-insha.

Diwan" translates to "bureau" or "department," and "Insha" means "composition" or "writing." So, Diwan-i-insha literally translates to "Bureau of Writing."
This department handled all official written communication for the Sultanate. This included:
Drafting and sending letters and decrees (farmans) to other rulers, provincial governors, and officials.
Preparing official documents like treaties and administrative records.
Maintaining communication with foreign dignitaries and ambassadors.