Detailed Solution:
The correct answer is “1, 3, 4, 2, 5 and 6”.
Emperor Ashoka's pilgrimage route typically followed the significant events in the life of Buddha.
1) Gaya (Bodh Gaya): This is where Buddha attained enlightenment.
2) Kushinagar: This is where Buddha died.
3) Lumbini: This is Buddha's birthplace.
4) Kapilavastu: This is where Buddha spent his early life.
5) Sarnath: This is where Buddha delivered his first sermon.
6) Sravasti: This was an important center of Buddhist activity during Buddha's lifetime.
Therefore, the most likely route Ashoka followed would be: Gaya, Kushinagar, Lumbini, Kapilavastu, Sarnath, and Sravasti.