The correct answer is C. Gonds.
Gonds are an indigenous people of central India. They are the largest tribal group in India, with a population of over 10 million. Gonds speak Gondi, a Dravidian language. Gondi is the official language of the Indian state of Telangana.
Koyas are an indigenous people of central India. They are a sub-group of the Gonds. Koyas speak Koyali, a Dravidian language. Koyali is not an official language of any Indian state.
Chenchus are an indigenous people of central India. They are a sub-group of the Gonds. Chenchus speak Chenchu, a Dravidian language. Chenchu is not an official language of any Indian state.
Lambadis are an indigenous people of central India. They are a nomadic people who speak Lambadi, a Dravidian language. Lambadi is not an official language of any Indian state.