Administration of Sher Shah Suri
Sher Shah Suri, the founder of the Suri Empire in North India, implemented a highly organized administrative system that was pivotal for the effective governance of his empire. His administration was characterized by various reforms, including the division into main departments.

Main Departments
Sher Shah Suri's administration was divided into **four main departments**, which were crucial for managing different aspects of governance. These departments helped streamline the administration and improve efficiency.

Key Departments
- **Revenue Department**:
Responsible for the collection of taxes and management of agricultural lands, this department ensured a steady income for the state.
- **Military Department**:
This department oversaw the recruitment, training, and management of the army, ensuring that the empire was defended against external threats.
- **Judiciary Department**:
The judiciary was responsible for maintaining law and order, addressing disputes, and administering justice, thereby instilling confidence among the populace.
- **Public Works Department**:
Focused on infrastructure development, this department managed the construction of roads, bridges, and irrigation systems, which were vital for economic growth.

Significance of the Division
The establishment of these four departments not only enhanced the efficiency of governance but also set a precedent for future administrations in India. Sher Shah’s model of administration emphasized accountability and systematic management, which contributed significantly to the stability and prosperity of his empire.
In conclusion, the correct answer is **four** main departments, reflecting Sher Shah Suri's innovative approach to administration and governance.