Explanation
India’s cave architecture is a unique form of ancient rock-cut architecture, primarily serving religious and monastic purposes. Ex-Ajanta Caves, Ellora Caves, Elephanta Caves (Maharashtra), Udayagiri Caves (Madhya Pradesh), Badami Caves (Karnataka) etc.
Option (a) is correct: The Ajanta Caves are a UNESCO World Heritage Site located in the Aurangabad district of Maharashtra. They are carved into a horseshoe-shaped cliff along the Waghora River. The caves are renowned for their exquisite Buddhist rock-cut architecture and paintings, dating from the 2nd century BCE to the 6th century CE.
Option (b) is incorrect: The Sanchi Stupa is located in the Raisen district of Madhya Pradesh near the town of Sanchi. It is not in the gorge of the Chambal River but on a hill near Betwa River. It is a UNESCO World Heritage Site and contains one of the oldest Buddhist stupas.
Option (c) is incorrect: The Pandu-Lena (Trirashmi) Caves are located near Nashik, Maharashtra.The closest river is the Godavari River, not Narmada. These are Buddhist rock-cut caves, dating from 1st century BCE to 6th century CE and have inscriptions related to the Satavahanas and Western Kshatrapas.
Option (d) is incorrect: The Amaravati Stupa is located in Guntur district, Andhra Pradesh. It is one of the largest Buddhist stupas in India built during the Satavahana period (2nd century BCE). It was rediscovered by Colin Mackenzie in 1797 and located on the banks of the Krishna River, not the Godavari River.