Some of the major Scheduled Tribes in Bihar include:

Santhal, Oraon, Munda
Gond, Bhil, Baiga
Naga, Kuki, Mizo
Khasi, Garo, Jaintia

The correct answer is: a) Santhal, Oraon, Munda.

Scheduled Tribes are indigenous peoples who are considered to be socially and economically disadvantaged. They are listed in the Indian Constitution as a way to protect their rights and interests.

The Santhal, Oraon, and Munda are three of the largest Scheduled Tribes in Bihar. They are all indigenous peoples who have lived in the region for centuries. They have their own unique cultures and languages.

The Santhal are the largest Scheduled Tribe in Bihar. They are estimated to number around 7 million people. They are concentrated in the Santhal Parganas region of the state. The Santhal are a tribal people who have their own unique culture and language. They are known for their strong sense of community and their traditional way of life.

The Oraon are the second largest Scheduled Tribe in Bihar. They are estimated to number around 3 million people. They are concentrated in the Ranchi and Palamau districts of the state. The Oraon are a tribal people who have their own unique culture and language. They are known for their strong sense of community and their traditional way of life.

The Munda are the third largest Scheduled Tribe in Bihar. They are estimated to number around 2 million people. They are concentrated in the Gumla, Simdega, and Lohardaga districts of the state. The Munda are a tribal people who have their own unique culture and language. They are known for their strong sense of community and their traditional way of life.

The other options are incorrect because they do not include any Scheduled Tribes that are found in Bihar.