The correct answer is Kutch.
Kutch is a region in the northwestern part of Gujarat, India. It is known for its salt production, which is carried out in the Rann of Kutch, a large salt marsh. The salt is produced by solar evaporation, and is a major source of income for the region.
Saurashtra is another region in Gujarat that is known for its salt production. However, the salt production in Saurashtra is not as extensive as in Kutch.
Panchmahal and Vadodara are two other regions in Gujarat, but they are not known for their salt production.
The Rann of Kutch is a large salt marsh located in the northwestern part of Gujarat, India. It is the largest salt marsh in India, and the second largest in Asia. The Rann of Kutch is a popular tourist destination, and is known for its wildlife, including flamingos, crocodiles, and wild ass.
Solar evaporation is a process of producing salt by evaporating seawater. The seawater is heated by the sun, and the water evaporates, leaving behind the salt. Solar evaporation is a sustainable method of producing salt, and is the main method used in Kutch.