1. The question asks to identify a modern tank among the given options.
2. Bhim is a Self-Propelled Howitzer system, based on the Arjun tank chassis, but primarily an artillery system, not a main battle tank.
3. Akash is a surface-to-air missile system.
4. Arjun is India's indigenous Main Battle Tank (MBT), developed by DRDO. It represents a modern tank design.
5. Prithvi is a surface-to-surface ballistic missile series.