What is a 'Gopuram' in the context of Vijayanagara Empire?

Gateway

The correct answer is Option (4) → Gateway

Gopurams were Royal Gateways. They can be seen from distance and showed the power of kings.  The raya gopurams or royal gateways were an important structure and must have been a mark of imperial authority. Krishnadeva Raya credited with the construction of the eastern gopuram of the Virupaksha temple.