The correct option is Gopuram.
Explanation
The Dravida style of temple architecture, prevalent in South India, is distinct for its enclosed temple complexes. Unlike the Nagara style of North India, Dravida temples are typically surrounded by a high boundary wall (prakara). The monumental entrance gateway situated in this enclosure wall is a defining feature of this style.
- Gopuram is Correct: The Gopuram is the monumental entrance tower in Dravida temple architecture. It is usually pyramidal in shape, tapering towards the top, and is often adorned with intricate sculptures of deities and mythological figures. In later periods, such as under the Vijayanagara and Nayaka rulers, the Gopurams became massive and often dwarfed the main temple tower (Vimana).
- Torana is Incorrect: A Torana is a free-standing ornamental archway, most commonly associated with Buddhist architecture (e.g., the Great Stupa at Sanchi). While arch-like structures exist in Hindu architecture, the specific term for the Dravida entrance tower is Gopuram.
- Jagamohana is Incorrect: Jagamohana refers to the assembly hall or mandapa in the Kalinga school of architecture (a sub-style of the Nagara style found in Odisha). It sits in front of the main sanctum (Deula).
- Shikhara is Incorrect: In the Nagara style (North India), the Shikhara is the curvilinear tower over the main shrine. However, in the Dravida style, the tower over the main shrine is called the Vimana. In Dravida terminology, "Shikhara" refers specifically to the crowning cupola or dome-shaped capstone placed at the very top of the Vimana.
Key Takeaway: In Dravida architecture, the Vimana is the tower above the main sanctum, while the Gopuram is the monumental tower at the entrance gateway of the temple enclosure.