The question asks for the state in India with the largest inland saline wetland.

Option 1, Gujarat, is incorrect. While Gujarat does have saline wetlands, especially in areas such as the Rann of Kutch, it is not the state with the largest inland saline wetland.

Option 2, Haryana, is incorrect. Haryana is primarily a land-locked and agriculture-heavy state and does not have significant saline wetland regions.

Option 3, Madhya Pradesh, is incorrect. Being situated in the central part of India, Madhya Pradesh is landlocked and known more for its forests and wildlife, rather than saline wetlands.

Option 4, Rajasthan, is the correct answer. Rajasthan houses the Sambhar Lake, which is the largest inland saline wetland in India. Sambhar Lake is a seasonal salt lake and has been designated as a Ramsar site, which are wetlands of international importance. This lake plays a significant role in the regional salt production and is also a key area for flamingo and other bird species` migration.