Which of the following statements is not correct?

The correct answer is Option 2 because the statement is factually incorrect regarding the demographic distribution of tribes in India.

According to the 2011 Census, the North-Eastern states (including Sikkim) account for only about 12% of India's total Scheduled Tribe (ST) population. In contrast, over 70% of the tribal population resides in Central India (the "Tribal Belt"), spanning states like Madhya Pradesh, Maharashtra, Odisha, and Jharkhand. While the North-East has a high percentage of tribals within its own population, it does not hold the majority of the country's total tribal numbers.

• Option 1: Correct. The Constitution (Article 366) defines STs as those deemed under Article 342, but lacks a specific criteria-based definition.
• Option 3: Correct. The Todas are a pastoral tribe indigenous to the Nilgiri Hills.
• Option 4: Correct. Lotha is a major Sino-Tibetan language spoken by the Lotha tribe in Nagaland.