The correct option is C Si-yu-ki, 630 CE
Hsuan Tsang was a Chinese traveller who visited India in 630 CE. In his travelogue, Si-yu-ki, he talks about life in the reign of Harshavardhana. Hsuan Tsang recorded that Harshavardhana personally managed the administration. He took a lot of measures to take care of his subjects and his people. For instance, only 1/4th of the tax he collected went to administration. The rest went into charities and rewards. Hsuan Tsang also observed that the people led simple lives and women were free in society.