The correct option is 2 and 3 only.
Explanation
The Sun Temple at Modhera (Gujarat) dates back to the early 11th century (1026 AD). It represents the zenith of the Solanki style (also known as the Maru-Gurjara style) of temple architecture, which flourished in Western India.
Statement 1 is Incorrect:
The Sun Temple at Modhera was built by Raja Bhima I of the Solanki Dynasty (Chalukyas of Gujarat) in 1026 AD. The Chandela rulers are associated with the temple architecture of Khajuraho in Central India, not the Solanki style of Gujarat.
Statement 2 is Correct:
While the exterior of the temple and the pillars of the sabha mandapa (assembly hall) are intricately carved, the walls of the central shrine (garbhagriha) are plain and devoid of carving. This contrast is a specific feature noted in the architectural study of this temple.
Statement 3 is Correct:
A distinct feature of the Modhera temple complex is the massive rectangular stepped tank located in front of the temple, known as the Surya Kund (or Rama Kund). This tank includes numerous small shrines adorning its steps and is an integral part of the temple's layout.
Key Takeaway:
The Modhera Sun Temple is a classic example of Solanki architecture, characterized by a massive stepped tank (Surya Kund), intricate exterior carvings, and a central shrine with plain walls, built by Bhima I.