The correct answer is option 2 i.e., 9Concept:India is a country of vast geographical expanse.In the north, it is bound by the lofty Himalayas.The Arabian Sea in the west.The Bay of Bengal in the east.The Indian Ocean in the south.Explanation:Tamilnadu is the southern state of India, Chennai (formerly known as Madras) is the State Capital of Tamilnadu.Tamil Nadu is the tenth largest Indian state by area and the sixth-largest by population(Census,2011). Neighbouring states of Tamil Nadu are Andhra Pradesh, Kerala, and Karnataka. ?Hence, The neighbouring States of Tamil Nadu are - Kerala, Karnataka and Andhra PradeshAdditional InformationIndian States / Union Territories with the coast on the Arabian Sea:Gujrat.Maharashtra.Goa.Daman and Diu.Karnataka.Kerela.Lakshwadeep.Dadra and Nagar Haveli.Indian States / Union Territories with the coast on the Bay of Bengal:West Bengal.Odisha.Andhra Pradesh.Tamil Nadu.Puducherry.Andaman and Nicobar Islands.