Explanation:

- The Dahsala system was introduced by Akbar, the Mughal emperor, as a part of his administrative reforms.

- Option 1: Diplomatic missions - This refers to diplomatic efforts between countries, not related to the Dahsala system.

- Option 2: Land revenue system - The Dahsala system was primarily a land revenue system that calculated taxes based on the average produce of the last ten years.

- Option 3: Export and import of stones - This involves trade activities, not applicable to the Dahsala system.

- Option 4: Cultural meet - Refers to gatherings related to cultural exchanges, unrelated to the Dahsala system.