The correct answer is Mahanadi.
The Mahanadi river valley is known for its prehistoric and archaeological sites. The most famous of these sites is the Bhimbetka rock shelters, which are a UNESCO World Heritage Site. The Bhimbetka rock shelters contain some of the earliest known cave paintings in India, dating back to the Paleolithic period. The paintings depict a variety of animals, including tigers, elephants, and rhinoceroses, as well as humans engaged in hunting, gathering, and other activities.
Other important archaeological sites in the Mahanadi river valley include the Udaygiri and Khandagiri caves, which are Buddhist rock-cut temples dating from the 2nd century BCE. The caves are decorated with intricate carvings and sculptures, and they provide valuable insights into the history and culture of ancient India.
The Mahanadi river valley is also home to a number of prehistoric sites, including the Chirand site, which is a Mesolithic settlement dating back to around 7000 BCE. The Chirand site has yielded a wealth of artifacts, including stone tools, pottery, and animal bones. These artifacts provide valuable information about the lives of early humans in India.
In conclusion, the Mahanadi river valley is a region of great archaeological and historical significance. The region is home to a number of important prehistoric and archaeological sites, which provide valuable insights into the history and culture of ancient India.