The correct answer is A. Oraon.
The Oraon are an indigenous people of India, Bangladesh, and Nepal. They are the largest tribal group in Jharkhand, India, and are also found in significant numbers in Bihar, Chhattisgarh, Odisha, West Bengal, and Assam. The Oraon speak the Kurukh language, which is a member of the Munda language family.
The Santhals are an indigenous people of India. They are the largest tribal group in Jharkhand, India, and are also found in significant numbers in West Bengal, Odisha, Bihar, Assam, and Chhattisgarh. The Santhals speak the Santhali language, which is a member of the Munda language family.
The Chero are an indigenous people of India. They are found in the states of Jharkhand, Bihar, and West Bengal. The Chero speak the Chero language, which is a member of the Munda language family.
The Ho are an indigenous people of India. They are found in the states of Jharkhand, Bihar, and Odisha. The Ho speak the Ho language, which is a member of the Munda language family.