Answer : 4. "Chalcolithic Period "
Explanation :

1. 'Banas Culture' of Rajasthan belongs to the Chalcolithic period.

2. Banas culture (2600 BC – 1900 BC): It developed in the valley of the Banas River in south-east Rajasthan. Its main site is Ahar on the outskirts of Ukraine, hence it is also known as Ahar culture.