Correct Option
The statement "North-East India accounts for a little over half of the country's tribal population" is not correct. While the North-Eastern states have a significant proportion of tribal population relative to their total population, the majority of India's Scheduled Tribe population in absolute numbers resides in the central and eastern regions. States such as Madhya Pradesh, Maharashtra, Odisha, Rajasthan, and Jharkhand collectively account for over 60% of the country's tribal population.
Incorrect Options
The Constitution of India does not provide a specific definition for 'Scheduled Tribe'. Instead, Article 342 empowers the President to specify the tribes or tribal communities, or parts of or groups within tribes or tribal communities, which shall for the purposes of this Constitution be deemed to be Scheduled Tribes in relation to that State or Union Territory, after consultation with the Governor of the concerned State. Therefore, statement (a) is correct.
The Todas are an indigenous pastoral community primarily inhabiting the Nilgiri Hills of Tamil Nadu. They are known for their unique culture and traditional buffalo herding practices. Therefore, statement (c) is correct.
Lotha is a Tibeto-Burman language spoken by the Lotha Naga people, an ethnic group predominantly found in the Wokha district of Nagaland, India. Therefore, statement (d) is correct.