Explanation:

- NABARD stands for the National Bank for Agriculture and Rural Development.

- It serves a crucial role in India's rural economy.

- Option 1: Serves as an apex funding agency

- NABARD provides financial assistance to banks for rural development.

- It funds infrastructure projects and supports agrarian sectors.

- Option 2: Coordinate the rural financing activities

- It coordinates with state governments, banks, and other entities.

- Ensures smooth and effective deployment of financial resources.

- Option 3: Monitor and evaluate the refunded projects

- NABARD monitors funded projects for compliance and impact.

- It evaluates effectiveness and provides feedback for improvements.

- Option 4: All of these

- NABARD undertakes all the above functions.

- It serves a multifaceted role to boost rural economy.