Correct Option: C

Doab is a term used in India and Pakistan for a "tongue" or tract of land lying between two confluent rivers. Unqualified by the names of any rivers, it designates the flat alluvial tract between the Ganges and Yamuna rivers in western and southwestern Uttar Pradesh and Uttarakhand state in India, extending from the Sivalik Hills to the two rivers' confluence at Allahabad.