Answer : 3. "दक्षिण-पूर्व एशिया"
Explanation :

According to Avinash Chandra Das and Dr. Sampurnanand, the Arya Sapta came from the Saindhava region i.e. the north-western part of India. It has been called the Adidesh of the Aryans. Pandit Ganganath Jha told that Arya Brahmarshi had come from the country i.e. Burma, Thailand and Myanmar.