The correct option is B Hiuen Tsang
Hieun Tsang, the Chinese pilgrim, visited India during the reign of Harshavardhana with an aim of securing authentic Buddhist scripts. The Kannauj assembly (643 AD) was held in the honour of Hieun Tsang and to popularise Mahayana sect of Buddhism. Bāṇabhaṭṭa was a 7th-century Sanskrit prose writer and poet of India. He was the Asthana Kavi in the court of King Harsha Vardhana. Fa-hien was a Chinese pilgrim who visited India during the reign of Chandra Gupta II. Hence, these are incorrect.