Option a is the correct answer. The founder of the Karnata dynasty was Nanyadeva. He established the dynasty in 1097 CE. He was a Kayastha by caste and established his capital at Simraungadh. The dynasty controlled the region known as Tirhut or Mithila, located in present-day Bihar state of India and Nepal. Under the Karnats, Mithila enjoyed a significant degree of sovereignty from 1097 to 1324 CE. Nanyadeva's establishment of supremacy is believed to have been aided by Chalukya king Vikramaditya VI.