Answer the following question: Given the following passage  "In the 2nd century CE, Mahayana Sutras spread to China, and then to Korea and Japan, and were translated into Chinese. During the Indian period of Esoteric Buddhism (from the 8th century onwards), Buddhism spread from India to Tibet and Mongolia.",  answer the following question. Note that the answer is present within the text.  Question: What was rampant during the 10th century?
Answer:
Buddhism